Heat exchanger core for a printed circuit heat exchanger and printed circuit heat exchanger

Abstract

The present invention relates to a heat exchanger core (10) for a printed circuit heat exchanger (1) comprising: first heat exchanger plates (100) and second heat exchanger plates (200) alternatingly stacked onto each other in a stacking direction (S), and joined to each other. Each first and second heat exchanger plate (100, 200) comprises a pair of first port holes (150) and a pair of second port holes (160). Each first heat exchanger plate (100) comprises, a first heat exchange area (A1) comprising a first groove (102) forming a first passage (104) for a first media. Each second heat exchanger plate (200) comprises, a second heat exchange area (A2) comprising a second groove (202) forming a second passage (204) for a second media. One or more of the first heat exchanger plates (100) comprises a safety groove (500) arranged outside of the first heat exchange area (A1) and extending along at least a portion of a perimeter of the first heat exchange area (A1) so as to capture a leaked portion of the first media from the first heat exchange area (A1). The heat exchanger core (10) further comprises a first safety port (550) extending through the first heat exchanger plates (100) and the second heat exchanger plates (200) in the stacking direction (S). The safety groove (500) of the first heat exchanger plates (100) comprises at least a first outlet (502) communicating with the first safety port (550). A printed heat circuit heat exchanger (1) comprising the heat exchanger core (10) is also provided.

Description

Technical Field

[0001] The invention relates to the field of heat exchangers. More particularly, it is related to a heat exchanger core for a printed circuit heat exchanger, and to a printed circuit heat exchanger comprising such heat exchanger core.

[0002] The heat exchanger core has first heat exchanger plates and second heat exchanger plates alternatingly stacked onto each other in a stacking direction and joined to each other. Each first heat exchanger plate has a first heat exchange area having a passage for a first media and each second heat exchanger plate has heat exchange area having a passage for a second media.Background Art

[0003] Plate heat exchangers are used in numerous applications where heat is to be transferred from one fluid to another or vice versa. A typical plate heat exchanger includes a plate package or core formed of stacked heat exchanger plates.

[0004] One type of plate heat exchanger is the so-called printed circuit heat exchanger (PCHE). A PCHE generally has a core of a number of first heat exchanger plates and a number of second heat exchanger plates. The heat exchanger plates are typically stacked in an alternating fashion and joined to each other. Each first heat exchanger plate generally has a heat exchange area which includes passages formed by grooves, where the grooves are etched into the material of the heat exchanger plate. Correspondingly, each second heat exchanger plate generally has a heat exchange area which includes a number of passages formed by grooves, where the grooves are etched into the material of the heat exchanger plate.

[0005] The first heat exchanger plates and the second heat exchanger plates of a PCHE are typically joined to each other by a diffusion bonding process. In this way a strong bond is established between the respective heat exchanger plates. When heat exchanger plates are diffusion bonded to each other, a solid heat exchanger core with tailor-made passages can be formed. Given the strong bond between the heat exchanger plates, a PCHE is generally suitable for high pressure applications where the heat exchanger core is subjected to high working pressures which would risk breaking a regular plate heat exchanger in which the heat exchanger plates are patterned or shaped by being pressed or punched.

[0006] PCHEs are commonly used in hydrogen refueling stations due to their sturdy and pressure resistant nature. Although PCHEs have excellent resistance to high pressures, problems related to hydrogen leakage may still occur. Hydrogen is the lightest element and forms diatomic molecules when in a gaseous state. Given the small diatomic molecules of gaseous hydrogen small leaks of hydrogen are common. Hydrogen leakage in PCHEs can have different causes and is oftentimes hard to detect and to prevent. Further, since hydrogen mixed with air forms a highly flammable gas mixture leakage control is of utmost importance in order to not compromise safety. To this end, it has been suggested to provide additional plates between the first heat exchanger plates and the second heat exchanger plates, where the additional plates have structures for conveying away escaped hydrogen from the PCHE core. It has also been suggested to enclose the PCHE core in gas tight cover so as to capture escaped hydrogen.

[0007] The presence of further plates between the first heat exchanger plates and the second heat exchanger plates will for natural reasons reduce the performance of the PCHE, since any transfer of heat will have to occur through such further plates. Further, the introduction of further plates will result in that more material is needed for the PCHE. Thus, the PCHE will not only become larger and heavier but also more costly. In addition to this, the heat transfer area of the PCHE will have to be made larger to compensate for the lower performance. Further, if the PCHE is enclosed in a gas tight cover even more material is needed. At the same time, the PCHE becomes larger while service operations become more complicated and time consuming.

[0008] Hence, there is room for improvement when it comes to leakage control in PCHEs and in particular in the core of PCHEs.Summary

[0009] With the above in mind, it is an objective of the present invention to provide an improved heat exchange core for a printed circuit heat exchanger as well as a printed circuit heat exchanger including a heat exchange core.

[0010] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is capable of handling media leakage safely.

[0011] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is which is safe to use.

[0012] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is more efficient in terms material utilization.

[0013] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is which is safe to use while requiring less installation space.

[0014] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which has an improved overall performance.

[0015] Another object is to provide such a heat exchange core for a printed circuit heat exchanger which is easier to manufacture.

[0016] Another object is to provide such heat exchange core for a printed circuit heat exchanger which is more cost-effective.

[0017] To achieve at least one of the above objects and also other objects that will be evident from the following description, a heat exchanger core having the features defined in claim 1 is provided according to the present inventive concept. A printed circuit heat exchanger including a heat exchanger core for a printed circuit heat exchanger is provided according to claim 13.

[0018] More specifically, according to a first aspect, there is provided a heat exchanger core for a printed circuit heat exchanger comprising: first heat exchanger plates and second heat exchanger plates alternatingly stacked onto each other in a stacking direction, and joined to each other, wherein each first and second heat exchanger plate comprises a pair of first port holes and a pair of second port holes, wherein each first heat exchanger plate comprises a first heat exchange area comprising a first groove forming a first passage for a first media, the first passage extending between the first port holes of the first heat exchanger plate, wherein each second heat exchanger plate comprises a second heat exchange area comprising a second groove forming a second passage for a second media, the second passage extending between the second port holes of the second heat exchanger plate, wherein one or more of the first heat exchanger plates comprises a safety groove arranged outside of the first heat exchange area and extending along at least a portion of a perimeter of the first heat exchange area so as to capture a leaked portion of the first media from the first heat exchange area, and wherein the heat exchanger core further comprises a first safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction, and wherein the safety groove of the first heat exchanger plates comprises at least a first outlet communicating with the first safety port.

[0019] Hereby an improved heat exchanger core for a printed circuit heat exchanger is provided.

[0020] The heat exchanger core is designed for, and hence suitable to be used with, high pressures and large temperature differences. Further, the heat exchanger core is designed for great repeated cyclic temperature variations like when used in hydrogen refuelling stations.

[0021] Thus, the present invention is based on the realization that by providing a safety groove and a first safety port in the heat exchanger core a leaked portion of the first media may be captured. More specifically, the present invention is based on the realization that by providing a safety groove arranged outside of the first heat exchange area which extends along at least a portion of a perimeter of the first heat exchange area in one or more of the first heat exchanger plates in combination with a first safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction, a leaked portion of the first media from the first heat exchange area may be captured. In this way, such leaked portion may be taken care of in a safe way, thereby improving the overall safety of the heat exchanger core. This means in practice, that leak control may be added to the heat exchanger core without the need for adding any further elements, such as additional plates or housings. Furthermore, the heat exchanger core may be designed with more design freedom potentially resulting in a heat exchanger core which has an improved performance in terms of heat exchange.

[0022] In practice, leakage of the first media may have different causes. Moreover, the first media may leak from different locations of the heat exchanger core. However, leaks of the first media are typically related to the first heat exchange area although not necessarily being so. The fist media may for instance leak via imperfections in the material making up the first and second heat exchanger plates. The fist media may for instance leak via cracks formed in the first and second heat exchanger plates. The first media may for instance leak via areas or regions where a bonding, such as a diffusion bonding or diffusion welding, between the first and second heat exchanger plates is inferior or of a lower quality.

[0023] It should be noted that within the context of this application the term "safety groove" may here mean any groove which is disconnected from the first port holes and the second port holes which communicates with the first safety port. Further, the safety groove extends partially into its associated heat exchanger plate. Hence, a safety groove has a dept which corresponds to portion of a thickness of its associated heat exchanger plate. Thus, a safety groove does not extend through its associated heat exchanger plate. In other words, a safety groove extends along a major surface of its associated heat exchanger plate while at the same time not extending through the associated heat exchanger plate. A safety groove is isolated to its associated heat exchanger plate. A safety groove may lead its contents to the first safety port. Thus, a safety groove extends along a major surface of an associated heat exchanger plate. A safety groove is not in fluid communication with the first media or the second media between which heat is exchanged during use of the heat exchanger core. However, a leaked portion of the first media may be captured by a safety groove.

[0024] It should be noted that within the context of this application the term "safety port" or first safety port may here mean any type of port or opening which extends through the first heat exchanger plates and the second heat exchanger in the stacking direction which is disconnected from the first port holes and the second port holes while communicating with a safety groove.

[0025] Thus, by the provision of a safety groove in combination with a first safety port, leaked first media may be captured by the safety groove and lead to the first safety port. In this way, leaked first media may be handled in a safe and controlled manner. Thus, a portion of the first media being leaked from the first heat exchange area may reach the safety groove instead of exiting the heat exchanger core in an arbitrary uncontrolled fashion. Captured first media reaching the safety groove will in practice in turn reach the safety port via the first outlet.

[0026] It is further to be noted that leaked second media may be captured by the safety groove and lead to the first safety port.

[0027] One or more of the first heat exchanger plates comprises a safety groove arranged outside of the first heat exchange area and extending along at least a portion of a perimeter of the first heat exchange area. Thus, any number of the first heat exchanger plates may comprise a safety groove. However, each one of the first heat exchanger plates will typically be provided with a respective safety groove. In this way, a leaked portion of the first media being leaked from any first heat exchange area of any first heat exchange plate may be captured by a safety groove. Further, since the safety groove extends along at least a portion of the perimeter of the first heat exchange area, a leaked portion of the first media from the first heat exchange area may readily reach the safety groove.

[0028] By the heat exchanger core comprising a first safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction and wherein the safety groove of the first heat exchanger plates comprises at least a first outlet communicating with the safety port, a leaked portion of the first media captured by a safety groove in any one of the first plates may be lead to the first safety port via its associated first outlet. Hence, a leaked portion of the first media may reach the first safety port irrespective of from which first heat exchanger plate and from which location within the heat exchanger core it originates. According to an example, a leaked portion of the first media leaked from a central region of the heat exchanger core may reach the outside of the heat exchanger core via the first safety port.

[0029] The safety groove may extend along a major portion of the perimeter of the first heat exchange area, which is advantageous in that efficiency of the safety groove in terms of capturing leaked first media may be improved. In this way, the likelihood of leaked first media being captured by the safety groove may be significantly increased. Thus, the likelihood of leaked media escaping from the heat exchanger core in an arbitrary uncontrolled manner may be significantly reduced.

[0030] The safety groove, or the safety groove and the first safety port may jointly, circumscribe the first heat exchange area, which is advantageous in that efficiency of the safety groove in terms of capturing leaked first media may be further improved. In this way, the likelihood of leaked first media being captured may be further increased. Thus, the likelihood of leaked media escaping from the heat exchanger core in an arbitrary uncontrolled manner may be further reduced.

[0031] When the safety groove and the first safety port jointly circumscribe the first heat exchange area, the safety groove may further comprise a second outlet communicating with the first safety port, which is advantageous in that the safety groove and the first safety port may jointly circumscribe the first heat exchange area in an efficient way. To this end, a first end of the safety groove may communicate with the first safety port via the first outlet and a second end of the safety groove may communicate with the first safety port via the second outlet, while the safety groove extends outside of and along the perimeter of the first heat exchange area. Thus, the safety groove may extend from the first safety port to the first safety port while circumscribing the first heat exchange area apart from the distance occupied by the first safety port.

[0032] When the safety groove circumscribes the first heat exchange area, the safety groove may form a loop circumscribing the first heat exchange area, which is advantageous in that the safety groove may circumscribe the first heat exchange area without requiring more than the first outlet. Further, the safety groove may circumscribe the first heat exchange area without being affected, or without being substantially affected, by the presence of the first safety port. Furthermore, the safety groove may be provided close to the perimeter of the first heat exchange area without being affected by the location of the first safety port. In this way, the design freedom of the first heat exchanger plates and the second heat exchanger plates may be improved. According to an example, the safety port may be provided in a region of the first heat exchanger plates and the second heat exchanger plates where the performance in terms of heat transfer and strength is negatively affected to the smallest possible degree, or where the performance in terms of heat transfer and strength is not affected at all. At the same time, the safety groove may be provided in an optimal location, i.e. in a location where most needed. In other words, the safety groove may be provided in a location where the likelihood of capturing a leaked portion of the first media is maximized.

[0033] The heat exchanger core may further comprises a second safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction and being connected to the safety groove, wherein the safety groove comprises a first safety groove section and a second safety groove section, wherein the first safety groove section, the second safety groove section, the first safety port and the second safety port jointly circumscribe the first heat exchange area, which is advantageous in that a leaked portion of the first media may be led to more than one location of the heat exchanger core. To this end, the first safety groove section may comprise an outlet in communication with the first safety port and another outlet in communication with the second safety port. In other words, the first safety groove section may extend between the first safety port and the second safety port. Correspondingly, the second safety groove section may comprise an outlet in communication with the first safety port and another outlet in communication with the second safety port. In other words, the second safety groove section may extend between the first safety port and the second safety port. Further, in order for the first safety groove section, the second safety groove section, the first safety port and the second safety port to jointly circumscribe the first heat exchange area, the first safety groove section and the second safety groove section will typically extend between the first safety port and the second safety port outside different portions, e.g. outside opposite sides, of the first heat exchange area.

[0034] The safety groove may be arranged outside of the first port holes, and / or the safety groove may be arranged outside of the second port holes, which is advantageous in that also first media leaked from the first portholes may be captured by the safety groove. Further, in particular when the safety groove is arranged outside of the second port holes, second media leaked from the second port holes may be captured by the safety groove.

[0035] The safety groove may be arranged outside of the first port holes.

[0036] The safety groove may be arranged outside of the second port holes.

[0037] The safety groove may be arranged outside of the first port holes, and outside of the second port holes.

[0038] The safety groove may have a depth within a range corresponding to 20-90%, preferably 25-80%, more preferably 30-50% of a thickness of the associated first heat exchanger plate, which is advantageous in that an efficient safety groove capable of capturing a leaked portion of the first media may be provided while maintaining the strength of the heat exchanger core. Further, the safety groove may be fabricated simultaneously to fabricating the first groove and / or the second groove. Thus, no further manufacturing steps may be required for forming the safety groove.

[0039] The one or more of the first heat exchanger plates may comprise a set of safety grooves comprising the safety groove and at least one further safety groove configured in accordance with the above described safety groove, which is advantageous in that efficiency of the safety grooves of the set of safety grooves in terms of capturing leaked first media may be further improved. At the same time, the design freedom of the safety grooves of the set of safety grooves may be increased while maintaining a desired efficiency in terms of capturing leaked first media.

[0040] In general, the further safety groove may provide corresponding advantages as the safety groove.

[0041] The further safety groove may extend along a major portion of the perimeter of the first heat exchange area.

[0042] The further safety groove, or the further safety groove and the first safety port may jointly, circumscribe the first heat exchange area.

[0043] When the further safety groove and the first safety port jointly circumscribe the first heat exchange area, the further safety groove may further comprise a second outlet communicating with the first safety port.

[0044] When the further safety groove circumscribes the first heat exchange area, the further safety groove may form a loop circumscribing the first heat exchange area.

[0045] When the heat exchanger core comprises a second safety port, the second safety port may be connected to the further safety groove, wherein the further safety groove comprises a first further safety groove section and a second further safety groove section, wherein the first further safety groove section, the second further safety groove section, the first safety port and the second safety port jointly circumscribe the first heat exchange area.

[0046] The further safety groove may be arranged outside of the first port holes, and / or the further safety groove may be arranged outside of the second port holes.

[0047] The further safety groove may have a depth within a range corresponding to 20-90%, preferably 25-80%, more preferably 30-50% of a thickness of the associated first heat exchanger plate.

[0048] The one or more of the first heat exchanger plates may comprise a set of safety grooves comprising the safety groove and two or more further safety grooves configured in accordance with the above described safety groove.

[0049] One or more of the second heat exchanger plates may comprises a second safety groove arranged outside of the second heat exchange area and extending along at least a portion of a perimeter of the second heat exchange area so as to capture a leaked portion of the first media from the first heat exchange area, and wherein the second safety groove of the second heat exchanger plates may comprise at least a second safety groove outlet communicating with the first safety port.

[0050] In general, the second safety groove may provide corresponding advantages as the safety groove.

[0051] The second safety groove may extend along a major portion of the perimeter of the second heat exchange area.

[0052] The second safety groove, or the second safety groove and the first safety port may jointly, circumscribe the second heat exchange area.

[0053] The second safety groove may further comprise a further second safety groove outlet communicating with the first safety port, wherein the second safety groove and the first safety port jointly circumscribe the second heat exchange area.

[0054] When the second safety groove circumscribes the second heat exchange area, the second safety groove may form a loop circumscribing the second heat exchange area.

[0055] When the heat exchanger core comprises a second safety port, the second safety port may be connected to the second safety groove, wherein the second safety groove comprises a first second safety groove section and a second second safety groove section, wherein the first second safety groove section, the second second safety groove section, the first safety port and the second safety port jointly circumscribe the second heat exchange area.

[0056] The second safety groove may be arranged outside of the first port holes, and / or the second safety groove may be arranged outside of the second port holes.

[0057] The second safety groove may have a depth within a range corresponding to 20-90%, preferably 25-80%, more preferably 30-50% of a thickness of the associated second heat exchanger plate.

[0058] The one or more of the second heat exchanger plates may comprise a set of safety grooves comprising the second safety groove and two or more further second safety grooves configured in accordance with the above described second safety groove.

[0059] The first heat exchanger plates and second heat exchanger plates may be formed of a metal comprising material and the safety groove and, if present, the second safety groove may be formed by etching the metal comprising material.

[0060] The first heat exchanger plates and second heat exchanger plates may be formed of metal.

[0061] The first heat exchanger plates and second heat exchanger plates may be formed of a metal alloy.

[0062] The first heat exchanger plates and second heat exchanger plates may be formed of stainless steel.

[0063] The first heat exchanger plates and second heat exchanger plates may be formed of a nickel alloy.

[0064] The first heat exchanger plates and second heat exchanger plates may comprise titanium.

[0065] The safety groove may be formed by etching using a photoresist etch mask.

[0066] The safety groove may be formed by etching using a negative photoresist etch mask.

[0067] The safety groove may be formed simultaneously to forming the first groove.

[0068] The second safety groove may be formed by etching using a photoresist etch mask.

[0069] The second safety groove may be formed by etching using a negative photoresist etch mask.

[0070] The second safety groove may be formed simultaneously to forming the second groove.

[0071] The first heat exchanger plates and second heat exchanger plates may be joined by a diffusion bonding process.

[0072] The first heat exchanger plates and second heat exchanger plates may be joined by brazing.

[0073] The first heat exchanger plates and second heat exchanger plates may be joined by welding.

[0074] According to another aspect of the invention, there is provided a printed circuit heat exchanger comprising: a heat exchanger core according to the first aspect, a first end plate provided at a first end of the heat exchanger core as seen along the stacking direction, and a second end plate provided at a second end of the heat exchanger core as seen along the stacking direction, wherein one end plate of the first end plate and the second end plate, comprises a safety opening in fluid communication with the first safety port.

[0075] In general, features of this aspect provide similar advantages as discussed above in relation to the first aspect. Consequently, said advantages will not be repeated in order to avoid undue repetition.

[0076] It should be noted that within the context of this application the term "end plate" is here meant a plate of the heat exchanger that is void of a heat exchanger area. Hence, an end plate is void of grooves for the first media and for the second media. Further, an end plate is typically provided at an end of the heat exchanger core. In practice, a first end plate is typically provided at a fist end of the heat exchanger core as seen along the stacking direction, and a second end plate is typically provided at a second opposite end of the heat exchanger core as seen along the stacking direction. Further, an end plate may be formed of series of sub-plates stacked on top of each other. Such sub-plates may be of the same type or may for instance have different thicknesses or may be formed of different materials.

[0077] By the above design the first end plate may comprise zero or more openings. Correspondingly, the second end plate may comprise zero or more openings.

[0078] The first end plate may comprise the safety opening.

[0079] The second end plate may comprise the safety opening.

[0080] The safety opening may be in fluid communication with the second safety port if present.

[0081] One end plate of the first end plate and the second end plate may comprise a further safety opening in fluid communication with the second safety port if present.

[0082] A pressure sensor may be connected to the first safety opening, the pressure sensor being configured to measure a pressure in the first safety port, which is advantageous in that a leakage of the first media may be detected via an increased pressure in the first safety port. Thus, a leaked portion of the first media being captured by the safety groove will result in a pressure increase in the first safety port. By detecting such pressure increase, a leakage may be detected. In practice, a pressure increase in the first safety port related to a to a leakage of the first media will exceed a pressure increase in the in the first safety port related to an increased temperature of the heat exchanger core. In case the first media is hydrogen, the pressure of the first media is typically about 900 bar. A leakage of the first media at such a pressure will typically result in a pressure increase in the in the first safety port by far exceeding any pressure increase related to an increased temperature of the heat exchanger core. Further, in practice, a pressure increase in the in the first safety port exceeding a certain value may be considered indicative of a leakage of the first media. Further, in practice, a pressure in the first safety port exceeding a certain value may be considered indicative of a leakage of the first media.

[0083] The safety groove, the first safety port, if present, the second safety groove may be filled with an inert gas, such as argon, which is advantageous in that a captured leaked portion of the first media may be diluted in in the inert gas. In this way, such captured leaked portion of the first media may be rendered harmless or less harmless. For instance, in case the first media is hydrogen, the hydrogen may be diluted by the inert gas such that it cannot be ignited or becomes significantly more difficult to ignite. Correspondingly, in case the first media is toxic, the first media may be diluted and hence become less potent. Correspondingly, in case the first media is volatile, the first media may be diluted and hence become less potent.

[0084] The inert gas may comprise a dye, which is advantageous in that a leakage of the inert gas may be more easily observed.

[0085] The safety opening may be connected to a pressure regulating source, which is advantageous in that the pressure in the first safety port and hence in the safety groove may be set to a desired level. The pressure regulating source may be any type of source or device which is capable of setting or maintaining a pressure. The pressure regulating source may include a reservoir, such as a tank. The pressure regulating source may include a pump. The pressure regulating source may include a compressor. Other types of pressure regulating sources are conceivable.

[0086] By connecting the safety opening to a pressure regulating source, the pressure in the first safety port and hence in the safety groove may be set to a level which exceeds atmospheric pressure. In this way leakages from the first safety port and the safety groove to the ambient may result in a decreased pressure in the first safety port and hence in the safety groove. Thus, the tightness of the first safety port and hence in the safety groove may be probed by providing an overpressure to the first safety port and the safety groove.

[0087] Similarly, by connecting the safety opening to a pressure regulating source, the pressure in the first safety port and hence in the safety groove may be set to a level which is below atmospheric pressure. In this way, even a very limited amount of captured leaked first media may result in a pressure increase in the first safety port and hence in the safety groove. Thus, even very small leaks may readily be detected. Further, a pressure in the first safety port and hence in the safety groove which is below atmospheric pressure will assist in capturing a leaked portion of the first media.

[0088] Further, the pressure regulating source may be configured to reset the pressure in the first safety port and hence in the safety groove at regular intervals. In this way, the pressure in the first safety port and hence in the safety groove may be substantially maintained at a desired level even in case of minor leakage, such as an acceptable leakage, from the in the first safety port and the safety groove to the ambient.

[0089] The safety opening may be connected to a vacuum source, which is advantageous in that a captured leaked portion of the first media may be sucked away from the printed circuit heat exchanger and e.g. vented away or taken care of. Thus, in case the printed circuit heat exchanger is located in a confined space, such as a room or a housing, a captured leaked portion of the first media may be carried away and removed from the confined space. Further, connecting the safety opening to a vacuum source may assist in capturing leaked first media since the leaked first media will be sucked towards the safety groove and the first safety port.

[0090] One end plate, of the first end plate and the second end plate may comprise a first opening in fluid communication with a first port hole.

[0091] One end plate, of the first end plate and the second end plate may comprise a second opening in fluid communication with a second port hole.

[0092] The printed circuit heat exchanger may comprise a pair of first openings in fluid communication with a respective first port hole of the pair of first port holes of the heat exchanger core.

[0093] The printed circuit heat exchanger may comprise a pair of second openings in fluid communication with a respective second port hole of the pair of second port holes of the heat exchanger core.

[0094] Typically, the printed circuit heat exchanger will comprise a pair of first openings in fluid communication with a respective first port hole of the pair of first port holes of the heat exchanger core, and a pair of second openings in fluid communication with a respective second port hole of the pair of second port holes of the heat exchanger core. In this case, the first openings and the second openings may be arbitrary distributed between the first end plate and the second end plate. That is, zero or more of the first openings and the second openings may be provided at the first end plate. Correspondingly, zero or more of the first openings and the second openings may be provided at the second end plate. Both first openings may be provided at the fist end plate and both second openings may be provided at the second end plate.

[0095] A further scope of applicability of the present invention will become apparent from the detailed description given below. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from this detailed description.

[0096] Hence, it is to be understood that this invention is not limited to the particular component parts of the device described as such device may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only and is not intended to be limiting. It must be noted that, as used in the specification and the appended claim, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements unless the context clearly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, and the like. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.

[0097] Thus, throughout this specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.Brief Description of the Drawings

[0098] The above and other aspects of the present inventive concept will now be described in more detail, with reference to appended figures showing variants. The figures should not be considered limiting, instead, they are used for explaining and understanding.

[0099] As illustrated in the figures, the sizes of layers and regions may be exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of variants. Like reference numerals refer to like elements throughout. Fig. 1 is a is a schematic example perspective exploded view of a heat exchanger core for a printed circuit heat exchanger according to an embodiment. Fig. 2 is a schematic plane view of a first heat exchanger plate of the heat exchanger core of Fig. 1. Fig. 3 is a schematic plane view of a second heat exchanger plate of the heat exchanger core of Fig. 1. Fig. 4 is a is a schematic example perspective exploded view of a heat exchanger core for a printed circuit heat exchanger according to an embodiment. Fig. 5 is a schematic plane view of a first heat exchanger plate of the heat exchanger core of Fig. 4. Fig. 6 is a schematic plane view of a second heat exchanger plate of the heat exchanger core of Fig. 4. Figs. 7a-7h are schematic plane views of exemplary first heat exchanger plates which may be used in the heat exchanger cores of Figs. 1 and 4. Fig. 8 is a schematic example perspective exploded view of a printed circuit heat exchanger according to an embodiment. Detailed Description

[0100] The present inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred variants or embodiments of the inventive concept are shown. This inventive concept may, however, be implemented in many different forms and should not be construed as limited to the variants set forth herein; rather, these variants are provided for thoroughness and completeness, and fully convey the scope of the present inventive concept to the skilled person.

[0101] Example embodiments of heat exchanger core 10 for a printed circuit heat exchanger 1 will in the below be described with reference to the drawings. A printed circuit heat exchanger 1 will also be described with reference to the drawings. The drawings are only schematic and the relative dimensions of some structures and layers may be exaggerated and not drawn to scale. Rather the dimensions may be adapted for illustrational clarity and to facilitate understanding. When present in the figures, the indicated axes L and S consistently refer to lateral direction L of the heat exchanger core 10 and stacking direction S of the heat exchanger core 10. The term "lateral" direction L refers to any directions parallel to an extension plane of the heat exchanger plates of the heat exchanger core 10. The term "stacking" direction S refers to a direction parallel to a normal direction of the extension plane of the heat exchanger plates of the heat exchanger core 10.

[0102] Now turning to Figs. 1, 2 and 3. Fig 1 schematically illustrates by way of example an example heat exchanger core 10 for a printed circuit heat exchanger 1, such as the printed circuit heat exchanger 1 depicted in Fig. 8. Such core 10 may also be referred to as a plate package. The depicted heat exchanger core 10 will in the following generally be referred to as a core 10.

[0103] The core 10 is formed of a number of heat exchanger plates 100, 200. More specifically, the core 10 is formed by a number of first heat exchanger plates 100 and number second heat exchanger plates 200. The design of the first heat exchanger plates 100 of Fig 1. are illustrated in Fig. 2, to which reference is also made. Correspondingly, the design of the second heat exchanger plates 200 of Fig. 1 are illustrated in Fig. 3, to which reference is also made.

[0104] The first heat exchanger plates 100 and the second heat exchanger plates 200 are alternatingly stacked onto each other in a stacking direction S as illustrated in Fig. 1. It is to be noted that in Fig. 1, the first and second heat exchanger plates 100, 200 are illustrated as being separated in order to clearly illustrate the design of the heat exchanger plates 100, 200. However, as is to be understood, the first heat exchanger plates 100 and the second heat exchanger plates 200 are joined to each other to form the core 10.

[0105] The first and second heat exchanger plates 100, 200 are typically formed from metal plates or sheets. The metal plates form which the first and second heat exchanger plates 100, 200 are formed may for example be stainless steel plates. However, other materials such as various other metal alloys may be used to advantage. The first and second heat exchanger plates 100, 200 are typically joined to each other by a diffusion bonding process. Diffusion bonding as such is known in the art and will not be described in detail here. However, when the first and second heat exchanger plates 100, 200 are joined via a diffusion bonding process, the first and second heat exchanger plates 100, 200 are in short stacked onto each other and heated in a furnace under vacuum conditions while subjected to pressure. In this way, the first and second heat exchanger plates 100, 200 are joined to each other without using any solder or welding material.

[0106] However, before the first and second heat exchanger plates 100, 200 are joined to each other, the first and second heat exchanger plates 100, 200 are subjected to further processing steps aiming at forming the first and second heat exchanger plates 100, 200.

[0107] As illustrated in Figs. 1 and 2, each first heat exchanger plate 100 comprises a pair of first port holes 150 and a pair of second port holes 160. Correspondingly, as illustrated in Figs. 1 and 3, each second heat exchanger plate 200 comprises a pair of first port holes 150 and a pair of second port holes 160. As illustrated in Fig. 1, the first port holes 150 of the first heat exchanger plates 100 and of the second heat exchanger plates 200 are aligned so as to form a pair of port hole channels 152 (generally pointed out in Fig. 1) for a first media. Correspondingly, the second port holes 160 of the first heat exchanger plates 100 and of the second heat exchanger plates 200 are aligned so as to form a pair of port hole channels 162 (generally pointed out in Fig. 1) for a second media.

[0108] As illustrated in Figs. 1 and 2, each first heat exchanger plate 100 comprises, a first heat exchange area A1. The depicted first heat exchange area A1 of each first heat exchanger plate 100 comprises a plurality of first groves 102. The first grooves 102 are each forming a first passage 104 for the first media, i.e. the media associated with the first port hole channels 152. The first passages 104 are extending between the first portholes 150 of the associated first heat exchanger plate 100.

[0109] Correspondingly, as illustrated in Figs. 1 and 3, each second heat exchanger plate 200 comprises, a second heat exchange area A2. The depicted second heat exchange area A2 of each second heat exchanger plate 200 comprises a plurality of second grooves 202. The second grooves 202 are each forming a second passage 204 for the second media, i.e. the media associated with the second port hole channels 162. The second passages 204 are extending between the second portholes 160 of the associated second heat exchanger plate 200.

[0110] The depicted core 10 is designed to be used in a hydrogen refueling station. To this end, the first heat exchanger plates 100 comprises the first grooves 102 for feeding liquefied hydrogen, as a first media, between the first port holes 150 via the first heat exchange area A1. Correspondingly, the second heat exchanger plates 200 comprises the second grooves 202 for feeding a refrigerant, such as water, as a second media, between the second port holes 160 via the second heat exchange area A2. Thus, when the first media and the second media are fed via the first and second heat exchange areas A1, A2 heat will be exchanged between the first and second media depending on their temperatures. Typically, when the first media is liquefied hydrogen, the liquefied hydrogen will be cooled by the second media (water) while the medias are fed via the heat exchange areas A1, A2.

[0111] The depicted first grooves 102 and the second grooves 202 of Figs. 1, 2 and 3 are formed via an etching process in which the metal of the first and second heat exchanger plates 100, 200 are etched away to form a dedicated pattern of grooves, i.e. the first grooves 102 in case of a first heat exchanger plate 100 and the second grooves in case of a second heat exchanger plate 200. Metal etching as such is known in the art and will not be described in detail here. However, when etching the first grooves 102 and the second grooves 202, an etch mask formed of a photoresist is typically used. The photoresist may be a positive photoresist or a negative photoresist. A negative photoresist is generally desired due to its relatively speaking high resistance to the etch chemistry used to etch the grooves 102, 202. When etching the grooves 102, 202, a major surface of a plate 100, 200 to be etched is typically coated with a photoresist, whereafter the photoresist is exposed with the groove pattern to be etched in case of positive photoresist or with an inverse of the groove pattern to be etched in case of negative photoresist. The photoresist is then developed and used as an etch mask for the etch chemistry used to etch the metal at the major surface of the plate 100, 200 to be etched.

[0112] Further, as illustrated in Figs. 1 and 2, the first heat exchanger plates 100 of the core 10 comprises a respective safety groove 500. The depicted safety grooves 500 may like the first grooves 102 typically be etched into the material of the first heat exchanger plates 100. In other words, safety grooves 500 are typically etched into a major surface of the first heat exchanger plates 100. Further, the safety grooves 500 may be etched simultaneously to etching the first grooves 102. In this way, no additional manufacturing steps may be needed.

[0113] Further, any number of first heat exchanger plates 100 of the core 10 may be provided with a safety groove 500. Thus, a single first heat exchanger plate 100 may be provided with a safety groove 500. Correspondingly, two, three, four or ten first heat exchanger plates 100 may be provided with a safety groove 500 to give a few non-limiting examples. It is however preferred that all first heat exchanger plates 100 are provided with a respective safety groove 500, i.e. as illustrated in Fig. 1.

[0114] The design and location of the safety grooves 500 may vary. In this regard, different relevant designs and locations of safety grooves 500, second safety grooves 530 and further safety grooves 505a, 505b, 505c will be described in greater detail hereinafter while referring to Figs. 1-7h. In doing so, specific designs of the safety grooves 500 will be referred to as 500:X, where X denotes a particular design (and location) of a safety groove 500. The refence numeral 500 is still referring to all depicted safety grooves 500:X of any design. Thus, the refence numeral 500 is used where most convenient to e.g. increase the readability.

[0115] Despite the possible different designs and locations of the safety grooves 500 all described designs have several common design features. Such common design features include that a safety groove 500 is arranged outside of the first heat exchange area A1 of its associated first heat exchanger plate 100. Further, a safety groove 500 extends along at least a portion of a perimeter of the first heat exchange area A1 of its associated first heat exchanger plate 100. Further, the safety grooves 500 are grooves in the sense that they do not extend through a thickness of their associated first heat exchanger plates 100. Furthermore, safety grooves 500 are disconnected from the first port holes 150 and the second port holes 160. Thus, the first media and the second media will not enter into the safety grooves 500 and the second safety grooves 530 unless being leaked.

[0116] As best illustrated in Fig. 2, the safety groove 500:1 of the depicted first heat exchanger plate 100 is arranged outside of the first heat exchange area A1. Further, the safety groove 500:1 of the depicted first heat exchanger plate 100 extends along the perimeter of the first heat exchange area A1 so as to capture a leaked portion of the first media from the first heat exchange area A1. Thus, first media potentially leaked from the first heat exchange area A1 may, while trying to escape the core 10, be captured or at least partially captured by the safety groove 500:1. The design of the safety groove 500:1 will be described in greater detail further below.

[0117] Further, as illustrated in Figs. 1, 2 and 3, the core 10 comprises a first safety port 550 (generally pointed out in Fig. 1). As illustrated in Fig. 1, the first safety port 550 extends through the first heat exchanger plates 100 and the second heat exchanger plates 200 in the stacking direction S. Thus, the first heat exchanger plates 100 and the second heat exchanger plates 200 each comprise a respective hole (generally indicated as 550) for forming the first safety port 550. In other words, the first and second heat exchanger plates 100, 200 comprises a series of aligned or substantially aligned holes 550 forming the first safety port 550. It is to be noted that the first safety port 550 may be arranged in any suitable location of the first and second heat exchanger plates 100, 200.

[0118] Further, as illustrated in Fig. 2, the safety groove 500:1 and the first safety port 550 jointly, circumscribe the first heat exchange area A1. To this end, the safety groove 500:1 comprises a first outlet 502 communicating with the first safety port 550. Further, the safety groove 500:1 comprises a second outlet 504 communicating with the first safety port 550. By this design, first media leaked from the first heat exchange area A1 and being captured by the safety groove 500:1 may exit the safety groove 500:1 through the first outlet 502 or through the second outlet 504 and consequently reach the safety port 550.

[0119] The safety groove 500:1 of Fig. 2 has a generally rectangular shape and extends along respective edges of the first heat exchanger plates 100 while at the same time being arranged outside of the first heat exchange area A1 and extending along the perimeter of the first heat exchange area A1.

[0120] The depicted safety groove 500:1 of Fig. 2 is arranged outside of the first port holes 150. Thus, a leaked portion of the first media leaked from the first port holes 150 may be captured by the safety groove 500:1.

[0121] Further, the depicted safety groove 500:1 of Fig. 2 is arranged outside of the second port holes 160. Thus, a leaked portion of the second media leaked from the second port holes 150 may be captured by the safety groove 500:1, although this is typically not the main purpose of the safety groove 500:1.

[0122] According to embodiments, the safety groove 500 may extend along a portion of the perimeter of the second heat exchange area A1.

[0123] According to embodiments, the safety groove 500 may extend along at least a portion of the perimeter of the second heat exchange area A1.

[0124] According to embodiments, the safety groove 500 may extend along a major portion of the perimeter of the second heat exchange area A1.

[0125] As best illustrated in Fig. 3, the second heat exchanger plates 200 of the core 10 of Fig. 1 are void of any safety grooves 500.

[0126] Now turning to Figs. 4, 5, and 6. Fig 4 schematically illustrates by way of example an example heat exchanger core 10 of a design different from the design of Fig. 1. Figs. 5 and 6 illustrate first and second heat exchanger plates 100, 200 of the core 10 of Fig. 4. The core 10 of Fig. 4 is similar to the core 10 of Fig.1. Given the similarities, mainly differences will be described hereinafter to avoid undue repetition.

[0127] The first heat exchanger plates 100 of Figs. 4 and 5 are provided with a respective safety groove 500:2. The safety groove 500:2 is like the safety groove 500:1 arranged outside of the first heat exchange area A1. However, safety groove 500:2 circumscribes the first heat exchange area A1 by itself. More specifically, the safety groove 500:2 circumscribes the first heat exchange area A1 by forming a loop 510 circumscribing the first heat exchange area A1. Apart from the loop 510, the safety groove 500:2 includes a connection section 512. The connection section 512 extends between the loop 510 of the safety groove 500:2 and the first safety port 550. The connection section 510 comprises a first outlet 502 communicating with the first safety port 550.

[0128] Further, the safety groove 500:2 of Fig. 4 is arranged inside of the second port holes 160 as opposed to the safety groove 500:1 of Fig 2. In this way, the safety groove 500:2 may be arranged close to the first heat exchange area A1 as best illustrated in Fig. 5.

[0129] The second heat exchanger plates 200 of Figs. 4 and 6 are provided with a respective second safety groove 530. The depicted second safety grooves 530 are like the second grooves 202 etched into the material of the second heat exchanger plates 200. In other words, second safety grooves 530 are etched into a major surface of the second heat exchanger plates 200. The structure of the second safety grooves 530 generally corresponds to the structure of the safety grooves 500. Given this, mainly the layout on the surface of the second safety grooves 530 will be described below. As best illustrated in Fig. 6, the depicted second safety groove 530 of the second heat exchanger plate 200 is arranged outside of the second heat exchange area A2. Further, the second safety groove 530 of the depicted second heat exchanger plate 200 extends along the perimeter of the second heat exchange area A2 so as to capture a leaked portion of the first media from the first heat exchange area A1. Thus, first media potentially leaked from the first heat exchange area A1 may, while trying to escape the core 10, be captured or at least partially captured by the second safety groove 530. Thus, although the second safety groove 530 is provided in the second heat exchanger plate 200, the main purpose of the second safety groove is to capture leaked first media being leaked from the first heat exchange area A1 of a first heat exchanger plate 100. However, the second safety groove 530 may capture leaked second media.

[0130] Further, as illustrated in Fig. 2, the second safety groove 530 and the first safety port 550 jointly, circumscribe the second heat exchange area A2. To this end, the second safety groove 530 comprises a second safety groove outlet 532 communicating with the first safety port 550. Further, the second safety groove 530 comprises a further second safety groove outlet 534 communicating with the first safety port 550. By this design, first media leaked from the first heat exchange area A1 and being captured by the second safety groove 530 may exit the second safety groove 530 through the second safety groove outlet 532 or through the further second safety groove outlet 534 and consequently reach the first safety port 550.

[0131] The second safety groove 530 of Fig. 6 has a generally rectangular shape and extends along respective edges of the second heat exchanger plate 200 while at the same time being arranged outside of the second heat exchange area A2 and extending along the perimeter of the second heat exchange area A2.

[0132] The depicted second safety groove 530 of Fig. 6 is arranged outside of the first port holes 150. Thus, a leaked portion of the first media leaked from the first port holes 150 may be captured by the second safety groove 530.

[0133] Further, the depicted second safety groove 530 of Fig. 6 is arranged outside of the second port holes 160. Thus, a leaked portion of the second media leaked from the second port holes 150 and from the second heat exchange area A2 may be captured by the second safety groove 530, although this is typically not the main purpose of the second safety groove 530.

[0134] Further, any number of second heat exchanger plates 200 of the core 10 of Fig. 4 may be provided with a second safety groove 530. Thus, a single second heat exchanger plate 200 may be provided with a second safety groove 530. Correspondingly, two, three, four or ten second heat exchanger plates 200 may be provided with a second safety groove 530 to give a few non-limiting examples. It is however preferred that all second heat exchanger plates 200 are provided with a respective second safety groove 530, i.e. as illustrated in Fig. 4.

[0135] According to embodiments, the second safety groove 530 may extend along at least a portion of the perimeter of the second heat exchange area A2.

[0136] According to embodiments, the second safety groove 530 may extend along a major portion of the perimeter of the second heat exchange area A2.

[0137] Further, any number of second safety grooves 530 may be provided at one or more second heat exchanger plates 200.

[0138] As described above, the safety grooves 500 are to advantage formed by etching while etching the first grooves 102. Further, the second safety grooves 530 are to advantage formed by etching while etching the second grooves 202. The safety grooves 500 may typically be etched to have a depth within a range corresponding to 20-90%, preferably 25-80% of the thickness of the first heat exchanger plates 100. It is currently believed that a depth corresponding to 30-50% of the thickness of the associated first heat exchanger plate 100 provides for an optimal balance between strength of the core 10 and the capability of the safety groove 500 to feed leaked fist media or second media to the safety port 550. Irrespective of the fact the safety grooves 500 may be etched simultaneously to the first grooves 102, the depth of the safety grooves 500 may be adapted by tailoring a line width of the etch mask used for etching the first grooves 102 and the safety grooves 500, as is known in the art. Further, the above depths are equally valid for a second safety groove 530.

[0139] According to an example, the first and second heat exchanger plates 100, 200 may have a thickness in a range of 1,5 - 2,0 mm. In such case, the safety grooves 500 may be etched to have a depth of about 0,65 mm. However, the depth of the safety grooves 500 may be about 1,2 mm to improve the safety grooves 500 capability of leading leaked first media (and / or second media) to the first safety port 550. However, it is to be understood that any suitable thickness of the first and second heat exchanger plates 100, 200 may be used to advantage. Further, the above depths are equally valid for a second safety groove 530.

[0140] In the following a number of relevant designs of safety grooves 500 will be described with reference to Figs. 7a-7h. The safety groove 500 of Figs. 7a-7h are all exemplified as being arranged on a first heat exchanger plate 100. It is however to be understood that the designs of the safety grooves 500 of Figs. 7a-7h are also generally applicable to second safety grooves 530 of second heat exchanger plates 200.

[0141] Fig. 7a schematically illustrates a first heat exchanger plate 100 provided with a safety groove 500:3. The safety groove 500:3 is similar to the safety groove 500:1 of Fig. 2 but extends in a zig-zag fashion. Alternatively, or additionally, the safety groove 500:3 may extend in a wavy fashion, a curved fashion, or similar.

[0142] Fig. 7b schematically illustrates a first heat exchanger plate 100 provided with a safety groove 500:4. The safety groove 500:4 extends along a portion of the perimeter of the first heat exchange area A1. Further, the safety groove 500:3 is arranged inside of the lower second port hole 160 in Fig. 7b.

[0143] Fig. 7c schematically illustrates a first heat exchanger plate 100 provided with a safety groove 500:5. The safety groove 500:4 extends along a major portion of the perimeter of the first heat exchange area A1. Further, the safety groove 500:4 is arranged inside of the lower second port hole 160 and outside of the upper second port hole 160 in Fig. 7c.

[0144] Fig. 7d schematically illustrates a first heat exchanger plate 100 provided with a set of safety grooves comprising the safety groove 500:6 and a further safety groove 505a. The safety groove 500:6 is similar to the safety groove 500:1 of Fig. 2. The further safety groove 505a extends outside and in parallel to the safety groove 500:6.

[0145] Fig. 7e schematically illustrates a first heat exchanger plate 100 provided with a set of safety grooves comprising the safety groove 500:7 and a further safety groove 505b. The safety groove 500:7 is similar to the safety groove 500:1 of Fig. 2. The further safety groove 505b extends inside of the second port holes 160. Further, the further safety groove 505b extends along a major portion of the first heat exchange area A1.

[0146] Fig. 7f schematically illustrates a first heat exchanger plate 100 provided with a set of safety grooves comprising the safety groove 500:8 and a further safety groove 505c. The safety groove 500:8 is similar to the safety groove 500:1 of Fig. 2. The further safety groove 505c circumscribes the first heat exchange area A1 by itself by forming a loop circumscribing the first heat exchange area A1. Apart from the loop the further safety groove 505c includes a connection section extending between the loop and the first safety port 550. The connection section comprises an outlet communicating with the first safety port 550. Further, the further safety groove 505c of Fig. 7f is arranged inside of the second port holes 160 as opposed to the safety groove 500:8.

[0147] It is to be noted that that set of safety grooves may include any number of further safety grooves, such as 2, 3, 4, 5, 6 or 10 to give a few non-limiting examples.

[0148] In practice, the further safety grooves 505a, 505b, 505c described above may be configured in accordance with any safety groove 500 described herein.

[0149] In practice, any further safety groove may be configured in accordance with any safety groove 500 described herein.

[0150] Fig. 7g schematically illustrates a first heat exchanger plate 100 provided with a second safety port 560 apart from the fist safety port 550. The second safety port 560, just like the first safety port 550, extends through the first heat exchanger plates 100 and the second heat exchanger plates 200 of the core 10 in the stacking direction S, such as of the core 10 in Fig. 1 or 4. The second safety port 560 is connected to the safety groove 500:9. As depicted in Fig. 7g, the safety groove 500:9 comprises a first safety groove section 500:9a and a second safety groove section 500:9b. Hence, the safety groove 500:9 is jointly formed by the first safety groove section 500:9a and the second safety groove section 500:9b although being interrupted at the first safety port 550 at the second safety port 560. As further illustrated in Fig. 7g, the first safety groove section 500:9a, the second safety groove section 500:9b, the first safety port 550 and the second safety port 560 jointly circumscribe the first heat exchange area A1. Thus, a leaked portion of the first media captured by the first safety groove section 500:9a or the second safety groove section 500:9b may be lead to the first safety port 550 or to the second safety port 560.

[0151] It is to be noted that the first safety port 550 and the second safety port 560 may be arranged in any suitable location of the first and second heat exchanger plates 100, 200.

[0152] Fig. 7h schematically illustrates a first heat exchanger plate 100. The heat exchanger plate 100 of Fig 7h is similar to the heat exchanger plate 100 of Fig. 7g. However, the heat exchanger plate 100 of Fig 7h comprises two safety grooves 500:10 and 500:11. The safety groove 500:10 communicates with the first safety port 550 whereas the safety groove 500:11 communicates with second safety port 560. In this way first media captured by the safety groove 500:10 may be lead to the first safety port 550 whereas first media captured by the safety groove 500:11 may be lead to the second safety port 560.

[0153] Now turning to Fig. 8. Fig 8 illustrates by way of example a printed circuit heat exchanger 1. The depicted printed heat exchanger 1 of Fig. 8 comprises a core 10 of the type described above in conjunction with Figs. 1, 2 and 3. However, the printed heat exchanger 1 of Fig. 8 may comprise a core 10 of a different design. For instance, the printed heat exchanger 1 of Fig. 8 may comprise the core 10 described above in conjunction with Figs. 4, 5 and 6. Further the printed heat exchanger 1 of Fig. 8 may include any type of the first heat exchanger plates 100 described in conjunction with Figs. 7a-7h. Apart from the core 10, the printed heat exchanger 1 comprises a first end plate 300 and a second end plate 400. The first end plate is provided at a first end of the heat exchanger core 10 as seen along the stacking direction S. The second end plate 400 is provided at a second end of the heat exchanger core 10 as seen along the stacking direction S. Thus, the first end plate 300 and the second end plate 400 are provided at opposite ends of the core 10 as seen along the stacking direction S.

[0154] As illustrated in Fig. 8, the first end plate 300 comprises a pair of first openings 170 and a pair of second openings 180. The first openings 170 are in fluid communication with a respective port hole channel formed by the first port holes 150. Correspondingly, the second openings 180 are in fluid communication with a respective port hole channel formed by the second port holes 160. Thus, a first media may be fed into the core 10 via one of the first openings 170 and extracted from the core via the other one of the first openings 170. Hence, the first media may be fed between the first openings 170. Correspondingly, a second media may be fed into the core 10 via one of the second openings 180 and extracted from the core via the other one of the second openings 180. Hence, the second media may be fed between the second openings 180. In this way, heat may be exchanged between the first media and the second media.

[0155] Further, as illustrated in Fig. 8, the first end plate 300 comprises a safety opening 350 in fluid communication with the first safety port 550. Thus, a leaked portion of first media (and / or second media) captured by the safety grooves 500 of the first heat exchanger plates 100 of core 10 of Fig. 8 may be lead to the safety port 550 and further out of the core 10 via the safety opening 350. However, it is generally not desired to just let captured first media escape the core 10 via the safety opening 350. As discussed above, when the first media is hydrogen, leaked hydrogen poses a safety risk due to its highly flammable nature. Given this, various measures may be taken to handle leaked first media in a safe way and / or to detect a leakage of first media (and / or second media).

[0156] To this end, a pressure sensor 50 may be connected to the first safety opening 550 as schematically illustrated in Fig. 8. In this way, the pressure sensor 50 may measure the pressure in the first safety port 550. As explained above, when a leaked portion of the first media is captured by a safety groove 500 the pressure in the safety groove 500 and consequently in the first safety port 550 will increase. Thus, by measuring the pressure by means of the pressure sensor 50, a leakage of the first media may be detected as an increased pressure in the first safety port 550. The pressure sensor 50 may be of any suitable kind. The pressure sensor 50 may be an analog sensor, such as a mechanical gauge. The pressure sensor 50 may be a sensor with a digital or analog interface connected to a controller 80, such as the controller 80 being schematically illustrated in Fig. 8. Further, as explained above, a leaked first media will typically result in a significantly higher pressure increase in the safety port 550 as compared to a pressure increase emanating from a temperature increase of the core 10.

[0157] To add further safety to the heat printed circuit heat exchanger 1 of Fig. 8, the safety grooves 500 and the first safety port 550 may be filled with an inert gas, such as argon. In this way, a captured leaked portion of the first media may be diluted in in the inert gas, e.g., the argon. In this way, such captured leaked portion of the first media may be rendered harmless or less harmless. At the same time, the pressure in the inert gas may increase as have been described above. Thus, a leak may be detected irrespective of if the safety grooves 500 and the first safety port 550 are filled with an inert gas or not.

[0158] Furter, the inert gas may include a dye to further increase the detectability of a leakage.

[0159] Further, the safety opening 350 may be connected to a pressure regulating source 60 as schematically illustrated in Fig. 8. The pressure regulating source 60 may be of any suitable kind. Further, a valve 70 may to advantage be connected between the pressure regulating source 60 and the safety opening 350. In this way, the pressure may be set to a desired level in the first safety port 550 and hence in the safety groove 500. Further, by closing the valve 70 when the pressure regulating source 60 has set a desired pressure in the first safety port 550, even a very small portion of leaked first media captured by the safety groove 500 may be detected as a pressure increase detectable by the pressure sensor 50.

[0160] As an alternative, the pressure regulating source 60 may regulate the pressure slowly, i.e. softly, such that a desired pressure is maintained in the first safety port 550 over time but a small portion of leaked first media captured by the safety groove 500 may still be detected as a pressure increase detectable by the pressure sensor 50.

[0161] The valve 70 may be connected to the controller 80, such that the pressure in the first safety port 550 is set to a desired level at regular intervals.

[0162] According to an example, the pressure in the first safety port 550 and hence in the safety groove 500 may be set to a level below atmospheric pressure. In this way, even a very small portion of leaked first media captured by the safety groove 500 may be detected as a pressure increase detectable by the pressure sensor 50.

[0163] According to an example, the pressure in the first safety port 550 and hence in the safety groove 500 may be set to a level which exceeds atmospheric pressure. In this way, the tightness of the first safety port 550 and hence the safety groove 500 may be probed since a leak in the first safety port 550 or in the safety groove 500 will over time result in a decreased pressure in the first safety port.

[0164] The controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure measured by the pressure sensor 50 in the first safety port 550 exceeding a threshold.

[0165] Further, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure measured by the pressure sensor 50 in the first safety port 550 increases more rapidly than threshold.

[0166] Alternatively, the safety opening 350 may be connected to a vacuum source 65 generally depicted as the pressure regulating source 60 in Fig. 8. By connecting the first safety port 350 to vacuum source 65, a captured leaked portion of the first media may be sucked away from the heat exchanger 1 and for instance vented away out into the ambient. In this way the safety of the heat exchanger 1 may be increased.

[0167] Further, when the safety opening is connected to a vacuum source 65 a captured leaked portion of the first media may be detected as an increased pressure in the vacuum source 65. Furthermore, a captured leaked portion of the first media may be detected as an increased load of a vacuum pump included in vacuum source 65.

[0168] To this end, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure in the vacuum source 65 exceeding a threshold.

[0169] Further, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure in the vacuum source 65 increases more rapidly than threshold.

[0170] Further, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to a load of a vacuum pump of the vacuum source 65 exceeding a threshold.

[0171] It is to be understood, that in case the core 10, and hence the heat exchanger 1, includes one or more second safety grooves 530 and / or one or more further safety grooves 505a, 505b, 505c, the one or more second safety grooves 530 and / or one or more further safety grooves 505a, 505b, 505c may typically be connected to the first safety port.

[0172] Further, it is to be understood that in case the core 10, and hence the heat exchanger 1, included one or more second safety ports 560 apart from the first safety port 550, the one or more second safety ports may typically be in fluid communication with a respective safety opening provided in the first or second end plate 300, 400.

[0173] Further, it is to be understood that the safety opening 350, the first openings 170 and the second openings 180 do not need to be provided at the first end plate 300 as illustrated in Fig. 8. In practice, the first openings 170 may be provided at the first end plate 300 as illustrated in Fig. 8, or at the second end plate 400. Correspondingly, the safety opening 350 may be provided at the first end plate 300 or at the second end plate 400. Further, one of the first openings 170 may be provided at the fist end plate 300 and the other one of the first openings 170 may be provided at the second end plate 400. Correspondingly, the second openings 180 may be provided at the first end plate 300 as illustrated in Fig. 8, or at the second end plate 400. Further, one of the second openings 180 may be provided at the fist end plate 300 and the other one of the second openings 180 may be provided at the second end plate 400. For example, the first openings 170 and the second openings 180 may be provided at opposite end plates 300, 400. For example, the first openings 170 and one of the second openings 180 may be provided at the first end plate 300, whereas the other one of the second openings 180 may be provided at the second end plate 400. For example, the second openings 180 and one of the first openings 170 may be provided at the first end plate 300, whereas the other one of the first openings 170 may be provided at the second end plate 400.

[0174] It will be appreciated that the present inventive concept is not limited to the variants and examples shown. Several modifications and variations are thus conceivable within the scope of the invention which thus is defined by the appended claims.

Examples

Embodiment Construction

[0100]The present inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred variants or embodiments of the inventive concept are shown. This inventive concept may, however, be implemented in many different forms and should not be construed as limited to the variants set forth herein; rather, these variants are provided for thoroughness and completeness, and fully convey the scope of the present inventive concept to the skilled person.

[0101]Example embodiments of heat exchanger core 10 for a printed circuit heat exchanger 1 will in the below be described with reference to the drawings. A printed circuit heat exchanger 1 will also be described with reference to the drawings. The drawings are only schematic and the relative dimensions of some structures and layers may be exaggerated and not drawn to scale. Rather the dimensions may be adapted for illustrational clarity and to facilitate understanding. When p...

Technical Field

[0001] The invention relates to the field of heat exchangers. More particularly, it is related to a heat exchanger core for a printed circuit heat exchanger, and to a printed circuit heat exchanger comprising such heat exchanger core.

[0002] The heat exchanger core has first heat exchanger plates and second heat exchanger plates alternatingly stacked onto each other in a stacking direction and joined to each other. Each first heat exchanger plate has a first heat exchange area having a passage for a first media and each second heat exchanger plate has heat exchange area having a passage for a second media.Background Art

[0003] Plate heat exchangers are used in numerous applications where heat is to be transferred from one fluid to another or vice versa. A typical plate heat exchanger includes a plate package or core formed of stacked heat exchanger plates.

[0004] One type of plate heat exchanger is the so-called printed circuit heat exchanger (PCHE). A PCHE generally has a core of a number of first heat exchanger plates and a number of second heat exchanger plates. The heat exchanger plates are typically stacked in an alternating fashion and joined to each other. Each first heat exchanger plate generally has a heat exchange area which includes passages formed by grooves, where the grooves are etched into the material of the heat exchanger plate. Correspondingly, each second heat exchanger plate generally has a heat exchange area which includes a number of passages formed by grooves, where the grooves are etched into the material of the heat exchanger plate.

[0005] The first heat exchanger plates and the second heat exchanger plates of a PCHE are typically joined to each other by a diffusion bonding process. In this way a strong bond is established between the respective heat exchanger plates. When heat exchanger plates are diffusion bonded to each other, a solid heat exchanger core with tailor-made passages can be formed. Given the strong bond between the heat exchanger plates, a PCHE is generally suitable for high pressure applications where the heat exchanger core is subjected to high working pressures which would risk breaking a regular plate heat exchanger in which the heat exchanger plates are patterned or shaped by being pressed or punched.

[0006] PCHEs are commonly used in hydrogen refueling stations due to their sturdy and pressure resistant nature. Although PCHEs have excellent resistance to high pressures, problems related to hydrogen leakage may still occur. Hydrogen is the lightest element and forms diatomic molecules when in a gaseous state. Given the small diatomic molecules of gaseous hydrogen small leaks of hydrogen are common. Hydrogen leakage in PCHEs can have different causes and is oftentimes hard to detect and to prevent. Further, since hydrogen mixed with air forms a highly flammable gas mixture leakage control is of utmost importance in order to not compromise safety. To this end, it has been suggested to provide additional plates between the first heat exchanger plates and the second heat exchanger plates, where the additional plates have structures for conveying away escaped hydrogen from the PCHE core. It has also been suggested to enclose the PCHE core in gas tight cover so as to capture escaped hydrogen.

[0007] The presence of further plates between the first heat exchanger plates and the second heat exchanger plates will for natural reasons reduce the performance of the PCHE, since any transfer of heat will have to occur through such further plates. Further, the introduction of further plates will result in that more material is needed for the PCHE. Thus, the PCHE will not only become larger and heavier but also more costly. In addition to this, the heat transfer area of the PCHE will have to be made larger to compensate for the lower performance. Further, if the PCHE is enclosed in a gas tight cover even more material is needed. At the same time, the PCHE becomes larger while service operations become more complicated and time consuming.

[0008] Hence, there is room for improvement when it comes to leakage control in PCHEs and in particular in the core of PCHEs.Summary

[0009] With the above in mind, it is an objective of the present invention to provide an improved heat exchange core for a printed circuit heat exchanger as well as a printed circuit heat exchanger including a heat exchange core.

[0010] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is capable of handling media leakage safely.

[0011] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is which is safe to use.

[0012] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is more efficient in terms material utilization.

[0013] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which is which is safe to use while requiring less installation space.

[0014] Another objective is to provide such a heat exchange core for a printed circuit heat exchanger which has an improved overall performance.

[0015] Another object is to provide such a heat exchange core for a printed circuit heat exchanger which is easier to manufacture.

[0016] Another object is to provide such heat exchange core for a printed circuit heat exchanger which is more cost-effective.

[0017] To achieve at least one of the above objects and also other objects that will be evident from the following description, a heat exchanger core having the features defined in claim 1 is provided according to the present inventive concept. A printed circuit heat exchanger including a heat exchanger core for a printed circuit heat exchanger is provided according to claim 13.

[0018] More specifically, according to a first aspect, there is provided a heat exchanger core for a printed circuit heat exchanger comprising: first heat exchanger plates and second heat exchanger plates alternatingly stacked onto each other in a stacking direction, and joined to each other, wherein each first and second heat exchanger plate comprises a pair of first port holes and a pair of second port holes, wherein each first heat exchanger plate comprises a first heat exchange area comprising a first groove forming a first passage for a first media, the first passage extending between the first port holes of the first heat exchanger plate, wherein each second heat exchanger plate comprises a second heat exchange area comprising a second groove forming a second passage for a second media, the second passage extending between the second port holes of the second heat exchanger plate, wherein one or more of the first heat exchanger plates comprises a safety groove arranged outside of the first heat exchange area and extending along at least a portion of a perimeter of the first heat exchange area so as to capture a leaked portion of the first media from the first heat exchange area, and wherein the heat exchanger core further comprises a first safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction, and wherein the safety groove of the first heat exchanger plates comprises at least a first outlet communicating with the first safety port.

[0019] Hereby an improved heat exchanger core for a printed circuit heat exchanger is provided.

[0020] The heat exchanger core is designed for, and hence suitable to be used with, high pressures and large temperature differences. Further, the heat exchanger core is designed for great repeated cyclic temperature variations like when used in hydrogen refuelling stations.

[0021] Thus, the present invention is based on the realization that by providing a safety groove and a first safety port in the heat exchanger core a leaked portion of the first media may be captured. More specifically, the present invention is based on the realization that by providing a safety groove arranged outside of the first heat exchange area which extends along at least a portion of a perimeter of the first heat exchange area in one or more of the first heat exchanger plates in combination with a first safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction, a leaked portion of the first media from the first heat exchange area may be captured. In this way, such leaked portion may be taken care of in a safe way, thereby improving the overall safety of the heat exchanger core. This means in practice, that leak control may be added to the heat exchanger core without the need for adding any further elements, such as additional plates or housings. Furthermore, the heat exchanger core may be designed with more design freedom potentially resulting in a heat exchanger core which has an improved performance in terms of heat exchange.

[0022] In practice, leakage of the first media may have different causes. Moreover, the first media may leak from different locations of the heat exchanger core. However, leaks of the first media are typically related to the first heat exchange area although not necessarily being so. The fist media may for instance leak via imperfections in the material making up the first and second heat exchanger plates. The fist media may for instance leak via cracks formed in the first and second heat exchanger plates. The first media may for instance leak via areas or regions where a bonding, such as a diffusion bonding or diffusion welding, between the first and second heat exchanger plates is inferior or of a lower quality.

[0023] It should be noted that within the context of this application the term "safety groove" may here mean any groove which is disconnected from the first port holes and the second port holes which communicates with the first safety port. Further, the safety groove extends partially into its associated heat exchanger plate. Hence, a safety groove has a dept which corresponds to portion of a thickness of its associated heat exchanger plate. Thus, a safety groove does not extend through its associated heat exchanger plate. In other words, a safety groove extends along a major surface of its associated heat exchanger plate while at the same time not extending through the associated heat exchanger plate. A safety groove is isolated to its associated heat exchanger plate. A safety groove may lead its contents to the first safety port. Thus, a safety groove extends along a major surface of an associated heat exchanger plate. A safety groove is not in fluid communication with the first media or the second media between which heat is exchanged during use of the heat exchanger core. However, a leaked portion of the first media may be captured by a safety groove.

[0024] It should be noted that within the context of this application the term "safety port" or first safety port may here mean any type of port or opening which extends through the first heat exchanger plates and the second heat exchanger in the stacking direction which is disconnected from the first port holes and the second port holes while communicating with a safety groove.

[0025] Thus, by the provision of a safety groove in combination with a first safety port, leaked first media may be captured by the safety groove and lead to the first safety port. In this way, leaked first media may be handled in a safe and controlled manner. Thus, a portion of the first media being leaked from the first heat exchange area may reach the safety groove instead of exiting the heat exchanger core in an arbitrary uncontrolled fashion. Captured first media reaching the safety groove will in practice in turn reach the safety port via the first outlet.

[0026] It is further to be noted that leaked second media may be captured by the safety groove and lead to the first safety port.

[0027] One or more of the first heat exchanger plates comprises a safety groove arranged outside of the first heat exchange area and extending along at least a portion of a perimeter of the first heat exchange area. Thus, any number of the first heat exchanger plates may comprise a safety groove. However, each one of the first heat exchanger plates will typically be provided with a respective safety groove. In this way, a leaked portion of the first media being leaked from any first heat exchange area of any first heat exchange plate may be captured by a safety groove. Further, since the safety groove extends along at least a portion of the perimeter of the first heat exchange area, a leaked portion of the first media from the first heat exchange area may readily reach the safety groove.

[0028] By the heat exchanger core comprising a first safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction and wherein the safety groove of the first heat exchanger plates comprises at least a first outlet communicating with the safety port, a leaked portion of the first media captured by a safety groove in any one of the first plates may be lead to the first safety port via its associated first outlet. Hence, a leaked portion of the first media may reach the first safety port irrespective of from which first heat exchanger plate and from which location within the heat exchanger core it originates. According to an example, a leaked portion of the first media leaked from a central region of the heat exchanger core may reach the outside of the heat exchanger core via the first safety port.

[0029] The safety groove may extend along a major portion of the perimeter of the first heat exchange area, which is advantageous in that efficiency of the safety groove in terms of capturing leaked first media may be improved. In this way, the likelihood of leaked first media being captured by the safety groove may be significantly increased. Thus, the likelihood of leaked media escaping from the heat exchanger core in an arbitrary uncontrolled manner may be significantly reduced.

[0030] The safety groove, or the safety groove and the first safety port may jointly, circumscribe the first heat exchange area, which is advantageous in that efficiency of the safety groove in terms of capturing leaked first media may be further improved. In this way, the likelihood of leaked first media being captured may be further increased. Thus, the likelihood of leaked media escaping from the heat exchanger core in an arbitrary uncontrolled manner may be further reduced.

[0031] When the safety groove and the first safety port jointly circumscribe the first heat exchange area, the safety groove may further comprise a second outlet communicating with the first safety port, which is advantageous in that the safety groove and the first safety port may jointly circumscribe the first heat exchange area in an efficient way. To this end, a first end of the safety groove may communicate with the first safety port via the first outlet and a second end of the safety groove may communicate with the first safety port via the second outlet, while the safety groove extends outside of and along the perimeter of the first heat exchange area. Thus, the safety groove may extend from the first safety port to the first safety port while circumscribing the first heat exchange area apart from the distance occupied by the first safety port.

[0032] When the safety groove circumscribes the first heat exchange area, the safety groove may form a loop circumscribing the first heat exchange area, which is advantageous in that the safety groove may circumscribe the first heat exchange area without requiring more than the first outlet. Further, the safety groove may circumscribe the first heat exchange area without being affected, or without being substantially affected, by the presence of the first safety port. Furthermore, the safety groove may be provided close to the perimeter of the first heat exchange area without being affected by the location of the first safety port. In this way, the design freedom of the first heat exchanger plates and the second heat exchanger plates may be improved. According to an example, the safety port may be provided in a region of the first heat exchanger plates and the second heat exchanger plates where the performance in terms of heat transfer and strength is negatively affected to the smallest possible degree, or where the performance in terms of heat transfer and strength is not affected at all. At the same time, the safety groove may be provided in an optimal location, i.e. in a location where most needed. In other words, the safety groove may be provided in a location where the likelihood of capturing a leaked portion of the first media is maximized.

[0033] The heat exchanger core may further comprises a second safety port extending through the first heat exchanger plates and the second heat exchanger plates in the stacking direction and being connected to the safety groove, wherein the safety groove comprises a first safety groove section and a second safety groove section, wherein the first safety groove section, the second safety groove section, the first safety port and the second safety port jointly circumscribe the first heat exchange area, which is advantageous in that a leaked portion of the first media may be led to more than one location of the heat exchanger core. To this end, the first safety groove section may comprise an outlet in communication with the first safety port and another outlet in communication with the second safety port. In other words, the first safety groove section may extend between the first safety port and the second safety port. Correspondingly, the second safety groove section may comprise an outlet in communication with the first safety port and another outlet in communication with the second safety port. In other words, the second safety groove section may extend between the first safety port and the second safety port. Further, in order for the first safety groove section, the second safety groove section, the first safety port and the second safety port to jointly circumscribe the first heat exchange area, the first safety groove section and the second safety groove section will typically extend between the first safety port and the second safety port outside different portions, e.g. outside opposite sides, of the first heat exchange area.

[0034] The safety groove may be arranged outside of the first port holes, and / or the safety groove may be arranged outside of the second port holes, which is advantageous in that also first media leaked from the first portholes may be captured by the safety groove. Further, in particular when the safety groove is arranged outside of the second port holes, second media leaked from the second port holes may be captured by the safety groove.

[0035] The safety groove may be arranged outside of the first port holes.

[0036] The safety groove may be arranged outside of the second port holes.

[0037] The safety groove may be arranged outside of the first port holes, and outside of the second port holes.

[0038] The safety groove may have a depth within a range corresponding to 20-90%, preferably 25-80%, more preferably 30-50% of a thickness of the associated first heat exchanger plate, which is advantageous in that an efficient safety groove capable of capturing a leaked portion of the first media may be provided while maintaining the strength of the heat exchanger core. Further, the safety groove may be fabricated simultaneously to fabricating the first groove and / or the second groove. Thus, no further manufacturing steps may be required for forming the safety groove.

[0039] The one or more of the first heat exchanger plates may comprise a set of safety grooves comprising the safety groove and at least one further safety groove configured in accordance with the above described safety groove, which is advantageous in that efficiency of the safety grooves of the set of safety grooves in terms of capturing leaked first media may be further improved. At the same time, the design freedom of the safety grooves of the set of safety grooves may be increased while maintaining a desired efficiency in terms of capturing leaked first media.

[0040] In general, the further safety groove may provide corresponding advantages as the safety groove.

[0041] The further safety groove may extend along a major portion of the perimeter of the first heat exchange area.

[0042] The further safety groove, or the further safety groove and the first safety port may jointly, circumscribe the first heat exchange area.

[0043] When the further safety groove and the first safety port jointly circumscribe the first heat exchange area, the further safety groove may further comprise a second outlet communicating with the first safety port.

[0044] When the further safety groove circumscribes the first heat exchange area, the further safety groove may form a loop circumscribing the first heat exchange area.

[0045] When the heat exchanger core comprises a second safety port, the second safety port may be connected to the further safety groove, wherein the further safety groove comprises a first further safety groove section and a second further safety groove section, wherein the first further safety groove section, the second further safety groove section, the first safety port and the second safety port jointly circumscribe the first heat exchange area.

[0046] The further safety groove may be arranged outside of the first port holes, and / or the further safety groove may be arranged outside of the second port holes.

[0047] The further safety groove may have a depth within a range corresponding to 20-90%, preferably 25-80%, more preferably 30-50% of a thickness of the associated first heat exchanger plate.

[0048] The one or more of the first heat exchanger plates may comprise a set of safety grooves comprising the safety groove and two or more further safety grooves configured in accordance with the above described safety groove.

[0049] One or more of the second heat exchanger plates may comprises a second safety groove arranged outside of the second heat exchange area and extending along at least a portion of a perimeter of the second heat exchange area so as to capture a leaked portion of the first media from the first heat exchange area, and wherein the second safety groove of the second heat exchanger plates may comprise at least a second safety groove outlet communicating with the first safety port.

[0050] In general, the second safety groove may provide corresponding advantages as the safety groove.

[0051] The second safety groove may extend along a major portion of the perimeter of the second heat exchange area.

[0052] The second safety groove, or the second safety groove and the first safety port may jointly, circumscribe the second heat exchange area.

[0053] The second safety groove may further comprise a further second safety groove outlet communicating with the first safety port, wherein the second safety groove and the first safety port jointly circumscribe the second heat exchange area.

[0054] When the second safety groove circumscribes the second heat exchange area, the second safety groove may form a loop circumscribing the second heat exchange area.

[0055] When the heat exchanger core comprises a second safety port, the second safety port may be connected to the second safety groove, wherein the second safety groove comprises a first second safety groove section and a second second safety groove section, wherein the first second safety groove section, the second second safety groove section, the first safety port and the second safety port jointly circumscribe the second heat exchange area.

[0056] The second safety groove may be arranged outside of the first port holes, and / or the second safety groove may be arranged outside of the second port holes.

[0057] The second safety groove may have a depth within a range corresponding to 20-90%, preferably 25-80%, more preferably 30-50% of a thickness of the associated second heat exchanger plate.

[0058] The one or more of the second heat exchanger plates may comprise a set of safety grooves comprising the second safety groove and two or more further second safety grooves configured in accordance with the above described second safety groove.

[0059] The first heat exchanger plates and second heat exchanger plates may be formed of a metal comprising material and the safety groove and, if present, the second safety groove may be formed by etching the metal comprising material.

[0060] The first heat exchanger plates and second heat exchanger plates may be formed of metal.

[0061] The first heat exchanger plates and second heat exchanger plates may be formed of a metal alloy.

[0062] The first heat exchanger plates and second heat exchanger plates may be formed of stainless steel.

[0063] The first heat exchanger plates and second heat exchanger plates may be formed of a nickel alloy.

[0064] The first heat exchanger plates and second heat exchanger plates may comprise titanium.

[0065] The safety groove may be formed by etching using a photoresist etch mask.

[0066] The safety groove may be formed by etching using a negative photoresist etch mask.

[0067] The safety groove may be formed simultaneously to forming the first groove.

[0068] The second safety groove may be formed by etching using a photoresist etch mask.

[0069] The second safety groove may be formed by etching using a negative photoresist etch mask.

[0070] The second safety groove may be formed simultaneously to forming the second groove.

[0071] The first heat exchanger plates and second heat exchanger plates may be joined by a diffusion bonding process.

[0072] The first heat exchanger plates and second heat exchanger plates may be joined by brazing.

[0073] The first heat exchanger plates and second heat exchanger plates may be joined by welding.

[0074] According to another aspect of the invention, there is provided a printed circuit heat exchanger comprising: a heat exchanger core according to the first aspect, a first end plate provided at a first end of the heat exchanger core as seen along the stacking direction, and a second end plate provided at a second end of the heat exchanger core as seen along the stacking direction, wherein one end plate of the first end plate and the second end plate, comprises a safety opening in fluid communication with the first safety port.

[0075] In general, features of this aspect provide similar advantages as discussed above in relation to the first aspect. Consequently, said advantages will not be repeated in order to avoid undue repetition.

[0076] It should be noted that within the context of this application the term "end plate" is here meant a plate of the heat exchanger that is void of a heat exchanger area. Hence, an end plate is void of grooves for the first media and for the second media. Further, an end plate is typically provided at an end of the heat exchanger core. In practice, a first end plate is typically provided at a fist end of the heat exchanger core as seen along the stacking direction, and a second end plate is typically provided at a second opposite end of the heat exchanger core as seen along the stacking direction. Further, an end plate may be formed of series of sub-plates stacked on top of each other. Such sub-plates may be of the same type or may for instance have different thicknesses or may be formed of different materials.

[0077] By the above design the first end plate may comprise zero or more openings. Correspondingly, the second end plate may comprise zero or more openings.

[0078] The first end plate may comprise the safety opening.

[0079] The second end plate may comprise the safety opening.

[0080] The safety opening may be in fluid communication with the second safety port if present.

[0081] One end plate of the first end plate and the second end plate may comprise a further safety opening in fluid communication with the second safety port if present.

[0082] A pressure sensor may be connected to the first safety opening, the pressure sensor being configured to measure a pressure in the first safety port, which is advantageous in that a leakage of the first media may be detected via an increased pressure in the first safety port. Thus, a leaked portion of the first media being captured by the safety groove will result in a pressure increase in the first safety port. By detecting such pressure increase, a leakage may be detected. In practice, a pressure increase in the first safety port related to a to a leakage of the first media will exceed a pressure increase in the in the first safety port related to an increased temperature of the heat exchanger core. In case the first media is hydrogen, the pressure of the first media is typically about 900 bar. A leakage of the first media at such a pressure will typically result in a pressure increase in the in the first safety port by far exceeding any pressure increase related to an increased temperature of the heat exchanger core. Further, in practice, a pressure increase in the in the first safety port exceeding a certain value may be considered indicative of a leakage of the first media. Further, in practice, a pressure in the first safety port exceeding a certain value may be considered indicative of a leakage of the first media.

[0083] The safety groove, the first safety port, if present, the second safety groove may be filled with an inert gas, such as argon, which is advantageous in that a captured leaked portion of the first media may be diluted in in the inert gas. In this way, such captured leaked portion of the first media may be rendered harmless or less harmless. For instance, in case the first media is hydrogen, the hydrogen may be diluted by the inert gas such that it cannot be ignited or becomes significantly more difficult to ignite. Correspondingly, in case the first media is toxic, the first media may be diluted and hence become less potent. Correspondingly, in case the first media is volatile, the first media may be diluted and hence become less potent.

[0084] The inert gas may comprise a dye, which is advantageous in that a leakage of the inert gas may be more easily observed.

[0085] The safety opening may be connected to a pressure regulating source, which is advantageous in that the pressure in the first safety port and hence in the safety groove may be set to a desired level. The pressure regulating source may be any type of source or device which is capable of setting or maintaining a pressure. The pressure regulating source may include a reservoir, such as a tank. The pressure regulating source may include a pump. The pressure regulating source may include a compressor. Other types of pressure regulating sources are conceivable.

[0086] By connecting the safety opening to a pressure regulating source, the pressure in the first safety port and hence in the safety groove may be set to a level which exceeds atmospheric pressure. In this way leakages from the first safety port and the safety groove to the ambient may result in a decreased pressure in the first safety port and hence in the safety groove. Thus, the tightness of the first safety port and hence in the safety groove may be probed by providing an overpressure to the first safety port and the safety groove.

[0087] Similarly, by connecting the safety opening to a pressure regulating source, the pressure in the first safety port and hence in the safety groove may be set to a level which is below atmospheric pressure. In this way, even a very limited amount of captured leaked first media may result in a pressure increase in the first safety port and hence in the safety groove. Thus, even very small leaks may readily be detected. Further, a pressure in the first safety port and hence in the safety groove which is below atmospheric pressure will assist in capturing a leaked portion of the first media.

[0088] Further, the pressure regulating source may be configured to reset the pressure in the first safety port and hence in the safety groove at regular intervals. In this way, the pressure in the first safety port and hence in the safety groove may be substantially maintained at a desired level even in case of minor leakage, such as an acceptable leakage, from the in the first safety port and the safety groove to the ambient.

[0089] The safety opening may be connected to a vacuum source, which is advantageous in that a captured leaked portion of the first media may be sucked away from the printed circuit heat exchanger and e.g. vented away or taken care of. Thus, in case the printed circuit heat exchanger is located in a confined space, such as a room or a housing, a captured leaked portion of the first media may be carried away and removed from the confined space. Further, connecting the safety opening to a vacuum source may assist in capturing leaked first media since the leaked first media will be sucked towards the safety groove and the first safety port.

[0090] One end plate, of the first end plate and the second end plate may comprise a first opening in fluid communication with a first port hole.

[0091] One end plate, of the first end plate and the second end plate may comprise a second opening in fluid communication with a second port hole.

[0092] The printed circuit heat exchanger may comprise a pair of first openings in fluid communication with a respective first port hole of the pair of first port holes of the heat exchanger core.

[0093] The printed circuit heat exchanger may comprise a pair of second openings in fluid communication with a respective second port hole of the pair of second port holes of the heat exchanger core.

[0094] Typically, the printed circuit heat exchanger will comprise a pair of first openings in fluid communication with a respective first port hole of the pair of first port holes of the heat exchanger core, and a pair of second openings in fluid communication with a respective second port hole of the pair of second port holes of the heat exchanger core. In this case, the first openings and the second openings may be arbitrary distributed between the first end plate and the second end plate. That is, zero or more of the first openings and the second openings may be provided at the first end plate. Correspondingly, zero or more of the first openings and the second openings may be provided at the second end plate. Both first openings may be provided at the fist end plate and both second openings may be provided at the second end plate.

[0095] A further scope of applicability of the present invention will become apparent from the detailed description given below. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from this detailed description.

[0096] Hence, it is to be understood that this invention is not limited to the particular component parts of the device described as such device may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only and is not intended to be limiting. It must be noted that, as used in the specification and the appended claim, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements unless the context clearly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, and the like. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.

[0097] Thus, throughout this specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.Brief Description of the Drawings

[0098] The above and other aspects of the present inventive concept will now be described in more detail, with reference to appended figures showing variants. The figures should not be considered limiting, instead, they are used for explaining and understanding.

[0099] As illustrated in the figures, the sizes of layers and regions may be exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of variants. Like reference numerals refer to like elements throughout. Fig. 1 is a is a schematic example perspective exploded view of a heat exchanger core for a printed circuit heat exchanger according to an embodiment. Fig. 2 is a schematic plane view of a first heat exchanger plate of the heat exchanger core of Fig. 1. Fig. 3 is a schematic plane view of a second heat exchanger plate of the heat exchanger core of Fig. 1. Fig. 4 is a is a schematic example perspective exploded view of a heat exchanger core for a printed circuit heat exchanger according to an embodiment. Fig. 5 is a schematic plane view of a first heat exchanger plate of the heat exchanger core of Fig. 4. Fig. 6 is a schematic plane view of a second heat exchanger plate of the heat exchanger core of Fig. 4. Figs. 7a-7h are schematic plane views of exemplary first heat exchanger plates which may be used in the heat exchanger cores of Figs. 1 and 4. Fig. 8 is a schematic example perspective exploded view of a printed circuit heat exchanger according to an embodiment. Detailed Description

[0100] The present inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred variants or embodiments of the inventive concept are shown. This inventive concept may, however, be implemented in many different forms and should not be construed as limited to the variants set forth herein; rather, these variants are provided for thoroughness and completeness, and fully convey the scope of the present inventive concept to the skilled person.

[0101] Example embodiments of heat exchanger core 10 for a printed circuit heat exchanger 1 will in the below be described with reference to the drawings. A printed circuit heat exchanger 1 will also be described with reference to the drawings. The drawings are only schematic and the relative dimensions of some structures and layers may be exaggerated and not drawn to scale. Rather the dimensions may be adapted for illustrational clarity and to facilitate understanding. When present in the figures, the indicated axes L and S consistently refer to lateral direction L of the heat exchanger core 10 and stacking direction S of the heat exchanger core 10. The term "lateral" direction L refers to any directions parallel to an extension plane of the heat exchanger plates of the heat exchanger core 10. The term "stacking" direction S refers to a direction parallel to a normal direction of the extension plane of the heat exchanger plates of the heat exchanger core 10.

[0102] Now turning to Figs. 1, 2 and 3. Fig 1 schematically illustrates by way of example an example heat exchanger core 10 for a printed circuit heat exchanger 1, such as the printed circuit heat exchanger 1 depicted in Fig. 8. Such core 10 may also be referred to as a plate package. The depicted heat exchanger core 10 will in the following generally be referred to as a core 10.

[0103] The core 10 is formed of a number of heat exchanger plates 100, 200. More specifically, the core 10 is formed by a number of first heat exchanger plates 100 and number second heat exchanger plates 200. The design of the first heat exchanger plates 100 of Fig 1. are illustrated in Fig. 2, to which reference is also made. Correspondingly, the design of the second heat exchanger plates 200 of Fig. 1 are illustrated in Fig. 3, to which reference is also made.

[0104] The first heat exchanger plates 100 and the second heat exchanger plates 200 are alternatingly stacked onto each other in a stacking direction S as illustrated in Fig. 1. It is to be noted that in Fig. 1, the first and second heat exchanger plates 100, 200 are illustrated as being separated in order to clearly illustrate the design of the heat exchanger plates 100, 200. However, as is to be understood, the first heat exchanger plates 100 and the second heat exchanger plates 200 are joined to each other to form the core 10.

[0105] The first and second heat exchanger plates 100, 200 are typically formed from metal plates or sheets. The metal plates form which the first and second heat exchanger plates 100, 200 are formed may for example be stainless steel plates. However, other materials such as various other metal alloys may be used to advantage. The first and second heat exchanger plates 100, 200 are typically joined to each other by a diffusion bonding process. Diffusion bonding as such is known in the art and will not be described in detail here. However, when the first and second heat exchanger plates 100, 200 are joined via a diffusion bonding process, the first and second heat exchanger plates 100, 200 are in short stacked onto each other and heated in a furnace under vacuum conditions while subjected to pressure. In this way, the first and second heat exchanger plates 100, 200 are joined to each other without using any solder or welding material.

[0106] However, before the first and second heat exchanger plates 100, 200 are joined to each other, the first and second heat exchanger plates 100, 200 are subjected to further processing steps aiming at forming the first and second heat exchanger plates 100, 200.

[0107] As illustrated in Figs. 1 and 2, each first heat exchanger plate 100 comprises a pair of first port holes 150 and a pair of second port holes 160. Correspondingly, as illustrated in Figs. 1 and 3, each second heat exchanger plate 200 comprises a pair of first port holes 150 and a pair of second port holes 160. As illustrated in Fig. 1, the first port holes 150 of the first heat exchanger plates 100 and of the second heat exchanger plates 200 are aligned so as to form a pair of port hole channels 152 (generally pointed out in Fig. 1) for a first media. Correspondingly, the second port holes 160 of the first heat exchanger plates 100 and of the second heat exchanger plates 200 are aligned so as to form a pair of port hole channels 162 (generally pointed out in Fig. 1) for a second media.

[0108] As illustrated in Figs. 1 and 2, each first heat exchanger plate 100 comprises, a first heat exchange area A1. The depicted first heat exchange area A1 of each first heat exchanger plate 100 comprises a plurality of first groves 102. The first grooves 102 are each forming a first passage 104 for the first media, i.e. the media associated with the first port hole channels 152. The first passages 104 are extending between the first portholes 150 of the associated first heat exchanger plate 100.

[0109] Correspondingly, as illustrated in Figs. 1 and 3, each second heat exchanger plate 200 comprises, a second heat exchange area A2. The depicted second heat exchange area A2 of each second heat exchanger plate 200 comprises a plurality of second grooves 202. The second grooves 202 are each forming a second passage 204 for the second media, i.e. the media associated with the second port hole channels 162. The second passages 204 are extending between the second portholes 160 of the associated second heat exchanger plate 200.

[0110] The depicted core 10 is designed to be used in a hydrogen refueling station. To this end, the first heat exchanger plates 100 comprises the first grooves 102 for feeding liquefied hydrogen, as a first media, between the first port holes 150 via the first heat exchange area A1. Correspondingly, the second heat exchanger plates 200 comprises the second grooves 202 for feeding a refrigerant, such as water, as a second media, between the second port holes 160 via the second heat exchange area A2. Thus, when the first media and the second media are fed via the first and second heat exchange areas A1, A2 heat will be exchanged between the first and second media depending on their temperatures. Typically, when the first media is liquefied hydrogen, the liquefied hydrogen will be cooled by the second media (water) while the medias are fed via the heat exchange areas A1, A2.

[0111] The depicted first grooves 102 and the second grooves 202 of Figs. 1, 2 and 3 are formed via an etching process in which the metal of the first and second heat exchanger plates 100, 200 are etched away to form a dedicated pattern of grooves, i.e. the first grooves 102 in case of a first heat exchanger plate 100 and the second grooves in case of a second heat exchanger plate 200. Metal etching as such is known in the art and will not be described in detail here. However, when etching the first grooves 102 and the second grooves 202, an etch mask formed of a photoresist is typically used. The photoresist may be a positive photoresist or a negative photoresist. A negative photoresist is generally desired due to its relatively speaking high resistance to the etch chemistry used to etch the grooves 102, 202. When etching the grooves 102, 202, a major surface of a plate 100, 200 to be etched is typically coated with a photoresist, whereafter the photoresist is exposed with the groove pattern to be etched in case of positive photoresist or with an inverse of the groove pattern to be etched in case of negative photoresist. The photoresist is then developed and used as an etch mask for the etch chemistry used to etch the metal at the major surface of the plate 100, 200 to be etched.

[0112] Further, as illustrated in Figs. 1 and 2, the first heat exchanger plates 100 of the core 10 comprises a respective safety groove 500. The depicted safety grooves 500 may like the first grooves 102 typically be etched into the material of the first heat exchanger plates 100. In other words, safety grooves 500 are typically etched into a major surface of the first heat exchanger plates 100. Further, the safety grooves 500 may be etched simultaneously to etching the first grooves 102. In this way, no additional manufacturing steps may be needed.

[0113] Further, any number of first heat exchanger plates 100 of the core 10 may be provided with a safety groove 500. Thus, a single first heat exchanger plate 100 may be provided with a safety groove 500. Correspondingly, two, three, four or ten first heat exchanger plates 100 may be provided with a safety groove 500 to give a few non-limiting examples. It is however preferred that all first heat exchanger plates 100 are provided with a respective safety groove 500, i.e. as illustrated in Fig. 1.

[0114] The design and location of the safety grooves 500 may vary. In this regard, different relevant designs and locations of safety grooves 500, second safety grooves 530 and further safety grooves 505a, 505b, 505c will be described in greater detail hereinafter while referring to Figs. 1-7h. In doing so, specific designs of the safety grooves 500 will be referred to as 500:X, where X denotes a particular design (and location) of a safety groove 500. The refence numeral 500 is still referring to all depicted safety grooves 500:X of any design. Thus, the refence numeral 500 is used where most convenient to e.g. increase the readability.

[0115] Despite the possible different designs and locations of the safety grooves 500 all described designs have several common design features. Such common design features include that a safety groove 500 is arranged outside of the first heat exchange area A1 of its associated first heat exchanger plate 100. Further, a safety groove 500 extends along at least a portion of a perimeter of the first heat exchange area A1 of its associated first heat exchanger plate 100. Further, the safety grooves 500 are grooves in the sense that they do not extend through a thickness of their associated first heat exchanger plates 100. Furthermore, safety grooves 500 are disconnected from the first port holes 150 and the second port holes 160. Thus, the first media and the second media will not enter into the safety grooves 500 and the second safety grooves 530 unless being leaked.

[0116] As best illustrated in Fig. 2, the safety groove 500:1 of the depicted first heat exchanger plate 100 is arranged outside of the first heat exchange area A1. Further, the safety groove 500:1 of the depicted first heat exchanger plate 100 extends along the perimeter of the first heat exchange area A1 so as to capture a leaked portion of the first media from the first heat exchange area A1. Thus, first media potentially leaked from the first heat exchange area A1 may, while trying to escape the core 10, be captured or at least partially captured by the safety groove 500:1. The design of the safety groove 500:1 will be described in greater detail further below.

[0117] Further, as illustrated in Figs. 1, 2 and 3, the core 10 comprises a first safety port 550 (generally pointed out in Fig. 1). As illustrated in Fig. 1, the first safety port 550 extends through the first heat exchanger plates 100 and the second heat exchanger plates 200 in the stacking direction S. Thus, the first heat exchanger plates 100 and the second heat exchanger plates 200 each comprise a respective hole (generally indicated as 550) for forming the first safety port 550. In other words, the first and second heat exchanger plates 100, 200 comprises a series of aligned or substantially aligned holes 550 forming the first safety port 550. It is to be noted that the first safety port 550 may be arranged in any suitable location of the first and second heat exchanger plates 100, 200.

[0118] Further, as illustrated in Fig. 2, the safety groove 500:1 and the first safety port 550 jointly, circumscribe the first heat exchange area A1. To this end, the safety groove 500:1 comprises a first outlet 502 communicating with the first safety port 550. Further, the safety groove 500:1 comprises a second outlet 504 communicating with the first safety port 550. By this design, first media leaked from the first heat exchange area A1 and being captured by the safety groove 500:1 may exit the safety groove 500:1 through the first outlet 502 or through the second outlet 504 and consequently reach the safety port 550.

[0119] The safety groove 500:1 of Fig. 2 has a generally rectangular shape and extends along respective edges of the first heat exchanger plates 100 while at the same time being arranged outside of the first heat exchange area A1 and extending along the perimeter of the first heat exchange area A1.

[0120] The depicted safety groove 500:1 of Fig. 2 is arranged outside of the first port holes 150. Thus, a leaked portion of the first media leaked from the first port holes 150 may be captured by the safety groove 500:1.

[0121] Further, the depicted safety groove 500:1 of Fig. 2 is arranged outside of the second port holes 160. Thus, a leaked portion of the second media leaked from the second port holes 150 may be captured by the safety groove 500:1, although this is typically not the main purpose of the safety groove 500:1.

[0122] According to embodiments, the safety groove 500 may extend along a portion of the perimeter of the second heat exchange area A1.

[0123] According to embodiments, the safety groove 500 may extend along at least a portion of the perimeter of the second heat exchange area A1.

[0124] According to embodiments, the safety groove 500 may extend along a major portion of the perimeter of the second heat exchange area A1.

[0125] As best illustrated in Fig. 3, the second heat exchanger plates 200 of the core 10 of Fig. 1 are void of any safety grooves 500.

[0126] Now turning to Figs. 4, 5, and 6. Fig 4 schematically illustrates by way of example an example heat exchanger core 10 of a design different from the design of Fig. 1. Figs. 5 and 6 illustrate first and second heat exchanger plates 100, 200 of the core 10 of Fig. 4. The core 10 of Fig. 4 is similar to the core 10 of Fig.1. Given the similarities, mainly differences will be described hereinafter to avoid undue repetition.

[0127] The first heat exchanger plates 100 of Figs. 4 and 5 are provided with a respective safety groove 500:2. The safety groove 500:2 is like the safety groove 500:1 arranged outside of the first heat exchange area A1. However, safety groove 500:2 circumscribes the first heat exchange area A1 by itself. More specifically, the safety groove 500:2 circumscribes the first heat exchange area A1 by forming a loop 510 circumscribing the first heat exchange area A1. Apart from the loop 510, the safety groove 500:2 includes a connection section 512. The connection section 512 extends between the loop 510 of the safety groove 500:2 and the first safety port 550. The connection section 510 comprises a first outlet 502 communicating with the first safety port 550.

[0128] Further, the safety groove 500:2 of Fig. 4 is arranged inside of the second port holes 160 as opposed to the safety groove 500:1 of Fig 2. In this way, the safety groove 500:2 may be arranged close to the first heat exchange area A1 as best illustrated in Fig. 5.

[0129] The second heat exchanger plates 200 of Figs. 4 and 6 are provided with a respective second safety groove 530. The depicted second safety grooves 530 are like the second grooves 202 etched into the material of the second heat exchanger plates 200. In other words, second safety grooves 530 are etched into a major surface of the second heat exchanger plates 200. The structure of the second safety grooves 530 generally corresponds to the structure of the safety grooves 500. Given this, mainly the layout on the surface of the second safety grooves 530 will be described below. As best illustrated in Fig. 6, the depicted second safety groove 530 of the second heat exchanger plate 200 is arranged outside of the second heat exchange area A2. Further, the second safety groove 530 of the depicted second heat exchanger plate 200 extends along the perimeter of the second heat exchange area A2 so as to capture a leaked portion of the first media from the first heat exchange area A1. Thus, first media potentially leaked from the first heat exchange area A1 may, while trying to escape the core 10, be captured or at least partially captured by the second safety groove 530. Thus, although the second safety groove 530 is provided in the second heat exchanger plate 200, the main purpose of the second safety groove is to capture leaked first media being leaked from the first heat exchange area A1 of a first heat exchanger plate 100. However, the second safety groove 530 may capture leaked second media.

[0130] Further, as illustrated in Fig. 2, the second safety groove 530 and the first safety port 550 jointly, circumscribe the second heat exchange area A2. To this end, the second safety groove 530 comprises a second safety groove outlet 532 communicating with the first safety port 550. Further, the second safety groove 530 comprises a further second safety groove outlet 534 communicating with the first safety port 550. By this design, first media leaked from the first heat exchange area A1 and being captured by the second safety groove 530 may exit the second safety groove 530 through the second safety groove outlet 532 or through the further second safety groove outlet 534 and consequently reach the first safety port 550.

[0131] The second safety groove 530 of Fig. 6 has a generally rectangular shape and extends along respective edges of the second heat exchanger plate 200 while at the same time being arranged outside of the second heat exchange area A2 and extending along the perimeter of the second heat exchange area A2.

[0132] The depicted second safety groove 530 of Fig. 6 is arranged outside of the first port holes 150. Thus, a leaked portion of the first media leaked from the first port holes 150 may be captured by the second safety groove 530.

[0133] Further, the depicted second safety groove 530 of Fig. 6 is arranged outside of the second port holes 160. Thus, a leaked portion of the second media leaked from the second port holes 150 and from the second heat exchange area A2 may be captured by the second safety groove 530, although this is typically not the main purpose of the second safety groove 530.

[0134] Further, any number of second heat exchanger plates 200 of the core 10 of Fig. 4 may be provided with a second safety groove 530. Thus, a single second heat exchanger plate 200 may be provided with a second safety groove 530. Correspondingly, two, three, four or ten second heat exchanger plates 200 may be provided with a second safety groove 530 to give a few non-limiting examples. It is however preferred that all second heat exchanger plates 200 are provided with a respective second safety groove 530, i.e. as illustrated in Fig. 4.

[0135] According to embodiments, the second safety groove 530 may extend along at least a portion of the perimeter of the second heat exchange area A2.

[0136] According to embodiments, the second safety groove 530 may extend along a major portion of the perimeter of the second heat exchange area A2.

[0137] Further, any number of second safety grooves 530 may be provided at one or more second heat exchanger plates 200.

[0138] As described above, the safety grooves 500 are to advantage formed by etching while etching the first grooves 102. Further, the second safety grooves 530 are to advantage formed by etching while etching the second grooves 202. The safety grooves 500 may typically be etched to have a depth within a range corresponding to 20-90%, preferably 25-80% of the thickness of the first heat exchanger plates 100. It is currently believed that a depth corresponding to 30-50% of the thickness of the associated first heat exchanger plate 100 provides for an optimal balance between strength of the core 10 and the capability of the safety groove 500 to feed leaked fist media or second media to the safety port 550. Irrespective of the fact the safety grooves 500 may be etched simultaneously to the first grooves 102, the depth of the safety grooves 500 may be adapted by tailoring a line width of the etch mask used for etching the first grooves 102 and the safety grooves 500, as is known in the art. Further, the above depths are equally valid for a second safety groove 530.

[0139] According to an example, the first and second heat exchanger plates 100, 200 may have a thickness in a range of 1,5 - 2,0 mm. In such case, the safety grooves 500 may be etched to have a depth of about 0,65 mm. However, the depth of the safety grooves 500 may be about 1,2 mm to improve the safety grooves 500 capability of leading leaked first media (and / or second media) to the first safety port 550. However, it is to be understood that any suitable thickness of the first and second heat exchanger plates 100, 200 may be used to advantage. Further, the above depths are equally valid for a second safety groove 530.

[0140] In the following a number of relevant designs of safety grooves 500 will be described with reference to Figs. 7a-7h. The safety groove 500 of Figs. 7a-7h are all exemplified as being arranged on a first heat exchanger plate 100. It is however to be understood that the designs of the safety grooves 500 of Figs. 7a-7h are also generally applicable to second safety grooves 530 of second heat exchanger plates 200.

[0141] Fig. 7a schematically illustrates a first heat exchanger plate 100 provided with a safety groove 500:3. The safety groove 500:3 is similar to the safety groove 500:1 of Fig. 2 but extends in a zig-zag fashion. Alternatively, or additionally, the safety groove 500:3 may extend in a wavy fashion, a curved fashion, or similar.

[0142] Fig. 7b schematically illustrates a first heat exchanger plate 100 provided with a safety groove 500:4. The safety groove 500:4 extends along a portion of the perimeter of the first heat exchange area A1. Further, the safety groove 500:3 is arranged inside of the lower second port hole 160 in Fig. 7b.

[0143] Fig. 7c schematically illustrates a first heat exchanger plate 100 provided with a safety groove 500:5. The safety groove 500:4 extends along a major portion of the perimeter of the first heat exchange area A1. Further, the safety groove 500:4 is arranged inside of the lower second port hole 160 and outside of the upper second port hole 160 in Fig. 7c.

[0144] Fig. 7d schematically illustrates a first heat exchanger plate 100 provided with a set of safety grooves comprising the safety groove 500:6 and a further safety groove 505a. The safety groove 500:6 is similar to the safety groove 500:1 of Fig. 2. The further safety groove 505a extends outside and in parallel to the safety groove 500:6.

[0145] Fig. 7e schematically illustrates a first heat exchanger plate 100 provided with a set of safety grooves comprising the safety groove 500:7 and a further safety groove 505b. The safety groove 500:7 is similar to the safety groove 500:1 of Fig. 2. The further safety groove 505b extends inside of the second port holes 160. Further, the further safety groove 505b extends along a major portion of the first heat exchange area A1.

[0146] Fig. 7f schematically illustrates a first heat exchanger plate 100 provided with a set of safety grooves comprising the safety groove 500:8 and a further safety groove 505c. The safety groove 500:8 is similar to the safety groove 500:1 of Fig. 2. The further safety groove 505c circumscribes the first heat exchange area A1 by itself by forming a loop circumscribing the first heat exchange area A1. Apart from the loop the further safety groove 505c includes a connection section extending between the loop and the first safety port 550. The connection section comprises an outlet communicating with the first safety port 550. Further, the further safety groove 505c of Fig. 7f is arranged inside of the second port holes 160 as opposed to the safety groove 500:8.

[0147] It is to be noted that that set of safety grooves may include any number of further safety grooves, such as 2, 3, 4, 5, 6 or 10 to give a few non-limiting examples.

[0148] In practice, the further safety grooves 505a, 505b, 505c described above may be configured in accordance with any safety groove 500 described herein.

[0149] In practice, any further safety groove may be configured in accordance with any safety groove 500 described herein.

[0150] Fig. 7g schematically illustrates a first heat exchanger plate 100 provided with a second safety port 560 apart from the fist safety port 550. The second safety port 560, just like the first safety port 550, extends through the first heat exchanger plates 100 and the second heat exchanger plates 200 of the core 10 in the stacking direction S, such as of the core 10 in Fig. 1 or 4. The second safety port 560 is connected to the safety groove 500:9. As depicted in Fig. 7g, the safety groove 500:9 comprises a first safety groove section 500:9a and a second safety groove section 500:9b. Hence, the safety groove 500:9 is jointly formed by the first safety groove section 500:9a and the second safety groove section 500:9b although being interrupted at the first safety port 550 at the second safety port 560. As further illustrated in Fig. 7g, the first safety groove section 500:9a, the second safety groove section 500:9b, the first safety port 550 and the second safety port 560 jointly circumscribe the first heat exchange area A1. Thus, a leaked portion of the first media captured by the first safety groove section 500:9a or the second safety groove section 500:9b may be lead to the first safety port 550 or to the second safety port 560.

[0151] It is to be noted that the first safety port 550 and the second safety port 560 may be arranged in any suitable location of the first and second heat exchanger plates 100, 200.

[0152] Fig. 7h schematically illustrates a first heat exchanger plate 100. The heat exchanger plate 100 of Fig 7h is similar to the heat exchanger plate 100 of Fig. 7g. However, the heat exchanger plate 100 of Fig 7h comprises two safety grooves 500:10 and 500:11. The safety groove 500:10 communicates with the first safety port 550 whereas the safety groove 500:11 communicates with second safety port 560. In this way first media captured by the safety groove 500:10 may be lead to the first safety port 550 whereas first media captured by the safety groove 500:11 may be lead to the second safety port 560.

[0153] Now turning to Fig. 8. Fig 8 illustrates by way of example a printed circuit heat exchanger 1. The depicted printed heat exchanger 1 of Fig. 8 comprises a core 10 of the type described above in conjunction with Figs. 1, 2 and 3. However, the printed heat exchanger 1 of Fig. 8 may comprise a core 10 of a different design. For instance, the printed heat exchanger 1 of Fig. 8 may comprise the core 10 described above in conjunction with Figs. 4, 5 and 6. Further the printed heat exchanger 1 of Fig. 8 may include any type of the first heat exchanger plates 100 described in conjunction with Figs. 7a-7h. Apart from the core 10, the printed heat exchanger 1 comprises a first end plate 300 and a second end plate 400. The first end plate is provided at a first end of the heat exchanger core 10 as seen along the stacking direction S. The second end plate 400 is provided at a second end of the heat exchanger core 10 as seen along the stacking direction S. Thus, the first end plate 300 and the second end plate 400 are provided at opposite ends of the core 10 as seen along the stacking direction S.

[0154] As illustrated in Fig. 8, the first end plate 300 comprises a pair of first openings 170 and a pair of second openings 180. The first openings 170 are in fluid communication with a respective port hole channel formed by the first port holes 150. Correspondingly, the second openings 180 are in fluid communication with a respective port hole channel formed by the second port holes 160. Thus, a first media may be fed into the core 10 via one of the first openings 170 and extracted from the core via the other one of the first openings 170. Hence, the first media may be fed between the first openings 170. Correspondingly, a second media may be fed into the core 10 via one of the second openings 180 and extracted from the core via the other one of the second openings 180. Hence, the second media may be fed between the second openings 180. In this way, heat may be exchanged between the first media and the second media.

[0155] Further, as illustrated in Fig. 8, the first end plate 300 comprises a safety opening 350 in fluid communication with the first safety port 550. Thus, a leaked portion of first media (and / or second media) captured by the safety grooves 500 of the first heat exchanger plates 100 of core 10 of Fig. 8 may be lead to the safety port 550 and further out of the core 10 via the safety opening 350. However, it is generally not desired to just let captured first media escape the core 10 via the safety opening 350. As discussed above, when the first media is hydrogen, leaked hydrogen poses a safety risk due to its highly flammable nature. Given this, various measures may be taken to handle leaked first media in a safe way and / or to detect a leakage of first media (and / or second media).

[0156] To this end, a pressure sensor 50 may be connected to the first safety opening 550 as schematically illustrated in Fig. 8. In this way, the pressure sensor 50 may measure the pressure in the first safety port 550. As explained above, when a leaked portion of the first media is captured by a safety groove 500 the pressure in the safety groove 500 and consequently in the first safety port 550 will increase. Thus, by measuring the pressure by means of the pressure sensor 50, a leakage of the first media may be detected as an increased pressure in the first safety port 550. The pressure sensor 50 may be of any suitable kind. The pressure sensor 50 may be an analog sensor, such as a mechanical gauge. The pressure sensor 50 may be a sensor with a digital or analog interface connected to a controller 80, such as the controller 80 being schematically illustrated in Fig. 8. Further, as explained above, a leaked first media will typically result in a significantly higher pressure increase in the safety port 550 as compared to a pressure increase emanating from a temperature increase of the core 10.

[0157] To add further safety to the heat printed circuit heat exchanger 1 of Fig. 8, the safety grooves 500 and the first safety port 550 may be filled with an inert gas, such as argon. In this way, a captured leaked portion of the first media may be diluted in in the inert gas, e.g., the argon. In this way, such captured leaked portion of the first media may be rendered harmless or less harmless. At the same time, the pressure in the inert gas may increase as have been described above. Thus, a leak may be detected irrespective of if the safety grooves 500 and the first safety port 550 are filled with an inert gas or not.

[0158] Furter, the inert gas may include a dye to further increase the detectability of a leakage.

[0159] Further, the safety opening 350 may be connected to a pressure regulating source 60 as schematically illustrated in Fig. 8. The pressure regulating source 60 may be of any suitable kind. Further, a valve 70 may to advantage be connected between the pressure regulating source 60 and the safety opening 350. In this way, the pressure may be set to a desired level in the first safety port 550 and hence in the safety groove 500. Further, by closing the valve 70 when the pressure regulating source 60 has set a desired pressure in the first safety port 550, even a very small portion of leaked first media captured by the safety groove 500 may be detected as a pressure increase detectable by the pressure sensor 50.

[0160] As an alternative, the pressure regulating source 60 may regulate the pressure slowly, i.e. softly, such that a desired pressure is maintained in the first safety port 550 over time but a small portion of leaked first media captured by the safety groove 500 may still be detected as a pressure increase detectable by the pressure sensor 50.

[0161] The valve 70 may be connected to the controller 80, such that the pressure in the first safety port 550 is set to a desired level at regular intervals.

[0162] According to an example, the pressure in the first safety port 550 and hence in the safety groove 500 may be set to a level below atmospheric pressure. In this way, even a very small portion of leaked first media captured by the safety groove 500 may be detected as a pressure increase detectable by the pressure sensor 50.

[0163] According to an example, the pressure in the first safety port 550 and hence in the safety groove 500 may be set to a level which exceeds atmospheric pressure. In this way, the tightness of the first safety port 550 and hence the safety groove 500 may be probed since a leak in the first safety port 550 or in the safety groove 500 will over time result in a decreased pressure in the first safety port.

[0164] The controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure measured by the pressure sensor 50 in the first safety port 550 exceeding a threshold.

[0165] Further, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure measured by the pressure sensor 50 in the first safety port 550 increases more rapidly than threshold.

[0166] Alternatively, the safety opening 350 may be connected to a vacuum source 65 generally depicted as the pressure regulating source 60 in Fig. 8. By connecting the first safety port 350 to vacuum source 65, a captured leaked portion of the first media may be sucked away from the heat exchanger 1 and for instance vented away out into the ambient. In this way the safety of the heat exchanger 1 may be increased.

[0167] Further, when the safety opening is connected to a vacuum source 65 a captured leaked portion of the first media may be detected as an increased pressure in the vacuum source 65. Furthermore, a captured leaked portion of the first media may be detected as an increased load of a vacuum pump included in vacuum source 65.

[0168] To this end, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure in the vacuum source 65 exceeding a threshold.

[0169] Further, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to the pressure in the vacuum source 65 increases more rapidly than threshold.

[0170] Further, the controller 80 may be configured to trigger an alarm and / or to stop operation of the heat exchanger 1 in response to a load of a vacuum pump of the vacuum source 65 exceeding a threshold.

[0171] It is to be understood, that in case the core 10, and hence the heat exchanger 1, includes one or more second safety grooves 530 and / or one or more further safety grooves 505a, 505b, 505c, the one or more second safety grooves 530 and / or one or more further safety grooves 505a, 505b, 505c may typically be connected to the first safety port.

[0172] Further, it is to be understood that in case the core 10, and hence the heat exchanger 1, included one or more second safety ports 560 apart from the first safety port 550, the one or more second safety ports may typically be in fluid communication with a respective safety opening provided in the first or second end plate 300, 400.

[0173] Further, it is to be understood that the safety opening 350, the first openings 170 and the second openings 180 do not need to be provided at the first end plate 300 as illustrated in Fig. 8. In practice, the first openings 170 may be provided at the first end plate 300 as illustrated in Fig. 8, or at the second end plate 400. Correspondingly, the safety opening 350 may be provided at the first end plate 300 or at the second end plate 400. Further, one of the first openings 170 may be provided at the fist end plate 300 and the other one of the first openings 170 may be provided at the second end plate 400. Correspondingly, the second openings 180 may be provided at the first end plate 300 as illustrated in Fig. 8, or at the second end plate 400. Further, one of the second openings 180 may be provided at the fist end plate 300 and the other one of the second openings 180 may be provided at the second end plate 400. For example, the first openings 170 and the second openings 180 may be provided at opposite end plates 300, 400. For example, the first openings 170 and one of the second openings 180 may be provided at the first end plate 300, whereas the other one of the second openings 180 may be provided at the second end plate 400. For example, the second openings 180 and one of the first openings 170 may be provided at the first end plate 300, whereas the other one of the first openings 170 may be provided at the second end plate 400.

[0174] It will be appreciated that the present inventive concept is not limited to the variants and examples shown. Several modifications and variations are thus conceivable within the scope of the invention which thus is defined by the appended claims.

Examples

Embodiment Construction

[0100]The present inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred variants or embodiments of the inventive concept are shown. This inventive concept may, however, be implemented in many different forms and should not be construed as limited to the variants set forth herein; rather, these variants are provided for thoroughness and completeness, and fully convey the scope of the present inventive concept to the skilled person.

[0101]Example embodiments of heat exchanger core 10 for a printed circuit heat exchanger 1 will in the below be described with reference to the drawings. A printed circuit heat exchanger 1 will also be described with reference to the drawings. The drawings are only schematic and the relative dimensions of some structures and layers may be exaggerated and not drawn to scale. Rather the dimensions may be adapted for illustrational clarity and to facilitate understanding. When p...

Claims

1. A heat exchanger core (10) for a printed circuit heat exchanger (1) comprising: first heat exchanger plates (100) and second heat exchanger plates (200) alternatingly stacked onto each other in a stacking direction (S), and joined to each other, wherein each first and second heat exchanger plate (100, 200) comprises a pair of first port holes (150) and a pair of second port holes (160), wherein each first heat exchanger plate (100) comprises a first heat exchange area (A1) comprising a first groove (102) forming a first passage (104) for a first media, the first passage (104) extending between the first port holes (150) of the first heat exchanger plate (100), wherein each second heat exchanger plate (200) comprises a second heat exchange area (A2) comprising a second groove (202) forming a second passage (204) for a second media, the second passage (204) extending between the second port holes (160) of the second heat exchanger plate (200), wherein one or more of the first heat exchanger plates (100) comprises a safety groove (500) arranged outside of the first heat exchange area (A1) and extending along at least a portion of a perimeter of the first heat exchange area (A1) so as to capture a leaked portion of the first media from the first heat exchange area (A1), and wherein the heat exchanger core (10) further comprises a first safety port (550) extending through the first heat exchanger plates (100) and the second heat exchanger plates (200) in the stacking direction (S), and wherein the safety groove (500) of the first heat exchanger plates (100) comprises at least a first outlet (502) communicating with the first safety port (550).

2. The heat exchanger core (10) according to claim 1, wherein the safety groove (500) extends along a major portion of the perimeter of the first heat exchange area (A1).

3. The heat exchanger core (10) according to claim 1 or 2, wherein the safety groove (500), or the safety groove (500) and the first safety port (550) jointly, circumscribe the first heat exchange area (A1).

4. The heat exchanger core (10) according to claim 3, wherein, when the safety groove (500) and the first safety port (550) jointly circumscribe the first heat exchange area (A1), the safety groove (500) further comprises a second outlet (504) communicating with the first safety port (550).

5. The heat exchanger core according to claim 3, wherein, when the safety groove (500) circumscribes the first heat exchange area (A1), the safety groove (500) forms a loop (510) circumscribing the first heat exchange area (A2).

6. The heat exchanger core (10) according to any one of the preceding claims, wherein the heat exchanger core (10) further comprises a second safety port (560) extending through the first heat exchanger plates (100) and the second heat exchanger plates (200) in the stacking direction (S) and being connected to the safety groove (500), wherein the safety groove (500) comprises a first safety groove section (500:9a) and a second safety groove section (500:9b), wherein the first safety groove section (500:9a), the second safety groove section (500:9b), the first safety port (550) and the second safety port (560) jointly circumscribe the first heat exchange area (A1).

7. The heat exchanger core (10) according to any one of the preceding claims, wherein the safety groove (500) is arranged outside of the first port holes (150), and / or wherein the safety groove (500) is arranged outside of the second port holes (160).

8. The heat exchanger core (10) according to any one of the preceding claims, wherein the safety groove (500) has a depth within a range corresponding to 20-90%, preferably 25-80%, more preferably 30-50% of a thickness of the associated first heat exchanger plate (100).

9. The heat exchanger core (10) according to any one of the preceding claims, wherein the one or more of the first heat exchanger plates (100) comprises a set of safety grooves comprising the safety groove (500) and at least one further safety groove (505a, 505b, 505c) configured in accordance with the safety groove (500) according to any one of the preceding claims.

10. The heat exchanger core (10) according to any one of the preceding claims, wherein one or more of the second heat exchanger plates (200) comprises a second safety groove (530) arranged outside of the second heat exchange area (A2) and extending along at least a portion of a perimeter of the second heat exchange area (A2) so as to capture a leaked portion of the first media from the first heat exchange area (A1), and wherein the second safety groove (530) of the second heat exchanger plates (200) comprises at least a second safety groove outlet (532) communicating with the first safety port (550).

11. The heat exchanger core (10) according to claim 10, wherein the second safety groove (530) extends along a major portion of the perimeter of the second heat exchange area (A2).

12. The heat exchanger core according to claim 10 or 11, wherein the second safety groove (530) further comprises a further second safety groove outlet (534) communicating with the first safety port (550), wherein the second safety groove (530) and the first safety port (550) jointly circumscribe the second heat exchange area (A2).

13. A printed circuit heat exchanger (1) comprising: a heat exchanger core (10) according to any one of the preceding claims, a first end plate (300) provided at a first end of the heat exchanger core (10) as seen along the stacking direction (S), and a second end plate (400) provided at a second end of the heat exchanger core (10) as seen along the stacking direction (S), wherein one end plate of the first end plate (300) and the second end plate (400), comprises a safety opening (350) in fluid communication with the first safety port (550).

14. The printed circuit heat exchanger (1) according to claim 13, wherein a pressure sensor (50) is connected to the first safety opening (550), the pressure sensor (50) being configured to measure a pressure in the first safety port (550).

15. The printed circuit heat exchanger (1) according to claim 13 or 14, wherein the safety groove (500), the first safety port (550) and, if present, the second safety groove (530) are filled with an inert gas, such as argon.

16. The printed circuit heat exchanger (1) according to any one of claims 13-15, wherein the safety opening (350) is connected to a pressure regulating source (60).

17. The printed circuit heat exchanger (1) according to any one of claims 13-15, wherein the safety opening (350) is connected to a vacuum source (65).

Images