A plate heat exchanger with varying flank inclinations
The plate heat exchanger with varying flank inclinations addresses inefficiencies in fluid distribution and heat transfer by optimizing fluid flow through varying flank angles, enhancing heat exchange efficiency.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SWEP INT AB
- Filing Date
- 2025-12-11
- Publication Date
- 2026-06-25
Smart Images
Figure SE2025010066_25062026_PF_FP_ABST
Abstract
Description
[0001] A PLATE HEAT EXCHANGER WITH VARYING FLANK INCLINATIONS
[0002] FIELD OF THE INVENTION
[0003] The present invention relates to a plate heat exchanger comprising a plurality of stacked heat exchanger plates having at least first, second, third and fourth port openings and a pattern of elongated and alternating ridges and grooves providing contact points between at least some crossing ridges and grooves of adjacent heat exchanger plates under formation of interplate flow channels for fluids to exchange heat, wherein the interplate flow channels are in selective fluid communication through the port openings, wherein each of the ridges has a top portion and each of the grooves has a bottom portion extending in a longitudinal direction of the ridges and grooves, and wherein said top and bottom portions are connected through opposite first and second flanks extending between the top and bottom portions and along the ridges and grooves.
[0004] PRIOR ART
[0005] Heat exchangers are used for exchanging heat between fluid media. They generally comprise a start plate, an end plate and a plurality of heat exchanger plates stacked onto one another in a manner forming flow channels between the heat exchanger plates by means of ridges of the heat exchanger plates contacting each other in contact points. The heat exchanger plates are provided with brazing material at least at or close to some of the contact points. Port openings are provided to allow selective fluid flow in and out from the flow channels in a way well known to persons skilled in the art. For example, two fluids are altematingly guided into the flow channels for exchange of heat between them. For example, port openings are arranged on different levels in relation to a general plane of the heat exchanger plates to altematingly form an opening for fluid and altematingly being closed by areas surrounding the port openings and contacting each other. Areas surrounding port openings and contacting each other can be connected by a brazing joint.
[0006] Before brazing, a plurality of heat exchanger plates are provided with a brazing material, after which the heat exchanger plates are stacked onto one another and placed in a furnace, wherein the heat exchanger plates are heated to a temperature sufficient to at least partially melt the brazing material or to connect the heat exchanger plates by diffusion bonding.
[0007] It is well known by persons skilled in the art that the flow channels between the heat exchanger plates of a plate heat exchanger are created by providing the heat exchanger plates with a pressed pattern of ridges and grooves. A plurality of heat exchanger plates are typically stacked on one another, wherein the ridges of a first heat exchanger plate contact the grooves of a neighboring second heat exchanger plate and general planes of the plates are thus kept at a distance from each other through contact points. Hence, flow channels are formed. In these flow channels, fluid media, such as a first and second fluid media are lead so that heat transfer is obtained between such media.
[0008] A plurality of brazed plate heat exchangers and heat exchanger plates with a pressed corrugated pattern having ridges and grooves is known in the prior art. The ridges and grooves have a top portion and a bottom portion and flanks extending between the top portions and the adjacent bottom portions. A variety of configurations of the ridges and grooves is known in the prior art. However, further improvement of the heat transfer of the plate heat exchangers is favorable.
[0009] SUMMARY OF THE INVENTION
[0010] One object of the present invention is to provide a heat exchanger plate with favorable heat exchange.
[0011] The present invention is related to a plate heat exchanger comprising a plurality of stacked first and second heat exchanger plates having a center axis, at least first, second, third and fourth port openings and a pattern of elongated and alternating ridges and grooves providing contact points between at least some crossing ridges and grooves of adjacent heat exchanger plates under formation of interplate flow channels for fluids to exchange heat, wherein the interplate flow channels are in selective fluid communication through the port openings, wherein each of the ridges has a top portion and each of the grooves has a bottom portion extending in a longitudinal direction of the ridges and grooves, and wherein said top and bottom portions are connected through opposite first and second flanks extending along the ridges and grooves, characterised in that an inclination of the first flank of at least some of the ridges and grooves differs from an inclination of the second flank thereof, and the inclination of said first flank varies along the ridges and grooves, and / or between different ridges and grooves.
[0012] The present invention results in favorable distribution of fluids and improved heat transfer. The different inclinations of the flanks makes it possible to guide the fluid flow in the interplate flow channels in a favorable manner for improved heat transfer. For example, the inclination of the first flanks can be bigger at the first port opening, which may be an inlet opening, than more remote from the first port opening to distribute the fluid in the interplate flow channel in an efficient manner. It is believed that this results in an increased pressure drop at the first port opening. Also, smaller volume in the interplate flow channel at the first port opening can be provided. Different volumes in different portions of the interplate flow channels and controlled pressure drop for distributing the fluid from the first port opening over the surface of the heat exchanger plates in a favorable manner and improved overall heat transfer of the plate heat exchanger is achieved. The first flank is closer to the first port opening than the second flank of the same ridge. Hence, the first flanks can be facing substantially towards the first port opening, wherein the second flanks are substantially facing away from the first port opening. The first flanks can be facing the general fluid flow direction in the interplate flow channel. Hence, at least at the first port opening, the fluid hits the first flank of a ridge before passing its top portion and comes into contact with the second flank of the same ridge. A plurality of ridges and grooves can be arranged with the varying inclination of the first flank and optionally also the second flank, wherein other ridges and grooves have flanks with constant inclination in the longitudinal direction of the ridges and grooves. The bigger inclination of the first flank in the vicinity of the first port opening may result in a smaller volume of the interplate flow channel in the vicinity of the first port opening compared to a more remote section of the interplate flow channel along the ridges and grooves. For a rectangular plate heat exchanger, the volume of the interplate flow channel can be smaller on the same side of the longitudinal centre axis as the first port opening, wherein the volume of the interplate flow channel can be bigger on the opposite side of the longitudinal centre axis. For example, a first longitudinal section of the ridge is on one side of the longitudinal centre axis and a second longitudinal section of the same ridge is on the other side of the longitudinal centre axis.
[0013] The inclination of the first flanks can decrease, e.g. continuously, along the ridges and grooves from one end, such as the end closer to the first port opening, to an opposite end, which opposite end may be more remote from the first port opening. For example, the inclination of the first flanks decreases along the first longitudinal section of the ridges. The inclination can also decrease along the second longitudinal section. Alternatively, said inclination is constant along the second longitudinal section.
[0014] The inclination of at least some of the first flanks can vary between different ridges and grooves. Hence, the inclination of the first flank of a first ridge can be different from the inclination of the first flank of a neighboring second ridge. This is favorable for controlling flow distribution in a direction across the ridges and grooves, such as in the longitudinal direction of a rectangular heat exchanger. For example, the inclination of the first flanks of different ridges and grooves can decrease in a direction from the first port opening to the second port opening. The first port opening can be an inlet for a first heat exchange fluid, such as a refrigerant, into a first interplate flow channel, and the second port opening can be an outlet for the same fluid out from the same interplate flow channel. The third and fourth port openings can be an inlet and outlet to a neighboring second flow channel for a second heat exchange fluid. The first and second flow channels can be arranged altematingly. Hence, the pressure drop and local interplate flow channel volume can be controlled in the general flow direction from the inlet to the outlet of the interplate flow channels.
[0015] The inclination of at least some of the second flanks can, in addition to or as an alternative to the first flanks, vary along the ridges and grooves to control the interplate flow channel volume and pressure drop in different areas of the interplate flow channels. For example, the inclination of the second flanks can decrease, optionally continuously, in one direction along the ridges and grooves to adapt the flow characteristics of the fluid in the interplate flow channels. For example, the second heat exchange fluid comes into contact with the second flank of a ridge first before passing the top portion thereof.
[0016] The inclination of at least some of the second flanks can, in addition to or as an alternative to the first flanks, vary between different ridges and grooves for controlling pressure drop and flow characteristics in the interplate flow channels in a direction across the ridges and grooves. Hence, the inclination of at least some of the second flanks can vary from one ridge to the next.
[0017] A width of at least some of the top portions can vary. The width of the top portions can vary along each of the ridges or each of a plurality of the ridges. Hence, the width of the top portions of some or all of the ridges can taper, e.g. in a direction away from the first port opening. The width of the top portions can be different in different sections of the heat exchanger plates. Hence, the width of at least some of the top portions can vary also between different ridges. Hence, the width of the top portion of one ridge can be different from the width of the top portion of another ridge.
[0018] The port openings form inlets and outlets for the fluids exchanging heat. The first port openings can form inlets for a first fluid to first interplate flow channels, wherein the second port openings can form outlets for the first fluid from the first interplate channels. Similarly, the third port openings can form inlets for a second fluid into second interplate flow channels, e.g. neighboring the first interplate flow channels, wherein the fourth port openings form the outlets for the second fluid from the second interplate flow channels. The port openings can be arranged near comers of the heat exchanger plates. The heat exchanger plates can be rectangular. The inclination of at least some of the first flanks can vary along the ridges and grooves, so that the inclination of the first flanks is bigger closer to the first port openings than more remote from the first port openings. Hence, the inclination at the inlets is bigger than at the outlets for one or both of the fluids, which will guide the fluid away from the inlets, such as generally in the lateral direction relative the general flow direction between the inlets and the outlets. Hence, instead of flowing the shortest way between the inlets and the outlets, the fluid can be guided to less accessible parts of the interplate flow channels in the lateral direction. For example, the inclination of the first flanks is decreasing in a direction from the first port opening to the third port opening of a heat exchanger plate, i.e. in the lateral direction. The inlets and outlets for the first fluid can be on a first side of the centre axis. In such a case, the inlets and outlets for the second fluid are on a second side of the centre axis opposite the first side. Alternatively, the inlets and outlets are arranged diagonally on the heat exchanger plates, i.e. on opposite sides of the center axis.
[0019] Optionally, the inclination of the first flanks of different ridges can also decrease in the heat exchange area from the first port opening to the second port opening of the same heat exchanger plate, wherein the inclination of the first flanks can increase in the heat exchange area from the third port opening to the fourth port opening of the same heat exchanger plate. Hence, in the first interplate flow channels, the first fluid is guided from the first port opening in the lateral direction towards the closed fourth port opening and then in a direction towards the closed third port opening to then be guided in the opposite lateral direction towards the second port opening.
[0020] The tops of the ridges can be wider closer to the inlets than more remotely from the inlets, such as more remotely in the lateral direction and / or the general flow direction, wherein the interplate flow channel volume is smaller closer to the inlets than more remotely from the inlets, such as laterally and / or in the general flow direction.
[0021] Further characteristics and advantages of the present invention will become apparent from the description of the embodiments below, the appended drawings and the dependent claims.
[0022] BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In the following, the invention will be described with reference to appended drawings, wherein:
[0024] Fig. 1 is a schematic and exploded perspective view of a plate heat exchanger comprising a plurality of first and second heat exchanger plates according to a first embodiment, Fig. 2 is a schematic and exploded view of a part of the plate heat exchanger of Fig. 1 , illustrating the first heat exchanger plate and the second heat exchanger plate more in detail,
[0025] Fig. 3 is a schematic and exploded perspective view of a plate heat exchanger according to a second embodiment,
[0026] Fig. 4 is a schematic and exploded view of a part of the plate heat exchanger of Fig. 3, illustrating the first heat exchanger plate and the second heat exchanger plate more in detail,
[0027] Fig. 5 is a schematic and exploded perspective view of a plate heat exchanger according to a third embodiment,
[0028] Fig. 6 is a schematic and exploded view of a part of the plate heat exchanger of Fig. 5, illustrating the first heat exchanger plate and the second heat exchanger plate more in detail,
[0029] Fig. 7 is a schematic front view of a heat exchanger plate of a plate heat exchanger according to a fourth embodiment,
[0030] Fig. 8 is a schematic perspective view of a heat exchanger plate of a plate heat exchanger according to a fifth embodiment,
[0031] Fig. 9 is a schematic perspective view of a heat exchanger plate of a plate heat exchanger according to a sixth embodiment,
[0032] Fig. 10 is a schematic section view of a part of a heat exchanger plate illustrating varying inclination profiles of different ridges and a symmetric ridge height in a first section,
[0033] Fig. 1 1 is a schematic section view of a part of a heat exchanger plate illustrating the varying inclination profiles of the ridges of Fig. 10 in a second section,
[0034] Fig. 12 is a schematic section view of a part of a heat exchanger plate illustrating varying inclination profiles of different ridges and an asymmetric ridge height in a first section, Fig. 13 is a schematic section view of a part of a heat exchanger plate illustrating the varying inclination profiles of the ridges of Fig. 12 in a second section,
[0035] Fig. 14 is a schematic view of a heat exchanger plate with varying inclination profiles of the ridges and a first chevron angle,
[0036] Fig. 15 is a schematic view of a heat exchanger plate with varying inclination profiles and a second chevron angle,
[0037] Fig. 16 is a schematic view of a heat exchanger plate with varying inclination profiles of the ridges, varying ridge heights and a first chevron angle, and
[0038] Fig. 17 is a schematic view of a heat exchanger plate with varying inclination profiles, varying ridge heights and a second chevron angle.
[0039] DESCRIPTION OF EMBODIMENTS
[0040] With reference to Fig. 1 an exploded view of a brazed plate heat exchanger 100 is illustrated according to a first embodiment. The heat exchanger 100 comprises a plurality of first heat exchanger plates 1 10 and a plurality of second heat exchanger plates 120 stacked in a stack to form the heat exchanger 100. The first and second heat exchanger plates 110, 120 are arranged altematingly, wherein every other plate is a first heat exchanger plate 110 and every other plate is a second heat exchanger plate 120. The first and second heat exchanger plates 1 10, 120 are different. Alternatively, the first and second heat exchanger plates 110, 120 may be similar, wherein one of the first and second heat exchanger plates 110, 120 has been rotated 180 degrees in relation to the other. In an alternative example (not illustrated), the first and second heat exchanger plates are arranged in another configuration together with additional heat exchanger plates, such as a third heat exchanger plate different from the first and second heat exchanger plates 110, 120. The heat exchanger plates 110, 120 are arranged to form interplate flow channels for fluids exchanging heat with each other.
[0041] In the illustrated embodiment, each of the heat exchanger plates 1 10, 120 comprises a skirt S, which extends almost perpendicular to a plane of the heat exchanger plate and is adapted to contact skirts of neighboring heat exchanger plates in order to provide a seal along the circumference of the heat exchanger 100. For example, the skirt S extends around the entire periphery of the heat exchanger pates 1 10, 120. Alternatively, the skirt S extends along at least two opposite sides of the heat exchanger plates 110, 120, such as long sides thereof, wherein the other sides may be connected through surfaces extending in the plane of the heat exchanger plates 110, 120. For example, the skirt S may be arranged in a conventional manner.
[0042] The heat exchanger plates 1 10, 120 are arranged with port openings 01 -04 for letting fluids to exchange heat into and out of the interplate flow channels. In the illustrated embodiment, the heat exchanger plates 110, 120 are arranged with a first port opening 01, a second port opening 02, a third port opening 03 and a fourth port opening 04. Areas surrounding the port openings O1 to 04 are provided at different heights such that selective communication between the port openings and the interplate flow channels is achieved. In the heat exchanger 100, the areas surrounding the port openings 01-04 are arranged such that the first and second port openings 01 and 02 are in fluid communication with one another through some interplate flow channels, whereas the third and fourth port openings 03 and 04 are in fluid communication with one another by other interplate flow channels. For example, the first and second port openings 01, 02 are arranged on the same side of a center axis, such as a longitudinal center axis, of the heat exchanger plates 1 10, 120, wherein the third and fourth port openings 03, 04 are arranged on the other side of the center axis. For example, the first port openings 01 form an inlet to first interplate flow channels for the first heat exchange fluid, wherein the second port openings 02 form an outlet from the first interplate flow channels or vice versa. Then, the fourth port openings 04 form an inlet to the second interplate flow channels for the second heat exchange fluid, wherein the third port openings 03 form an outlet from the second interplate flow channels or vice versa. In the illustrated embodiment, the heat exchanger plates 110, 120 are rectangular with rounded comers, wherein the port openings 01 -04 are arranged near the comers. Alternatively, the heat exchanger plates 110, 120 are square, e.g. with rounded comers. Alternatively, the heat exchanger plates 110, 120 are circular, oval or arranged with other suitable shape, wherein the port openings 01-04 are distributed in a suitable manner. In the illustrated embodiment, each of the heat exchanger plates 1 10, 120 is formed with four port openings 01-04. However in other embodiments of the invention (not illustrated), the number of port openings may be larger than four, i.e. six, eight or ten. For example, the number of port openings is at least six, wherein the heat exchanger is configured for providing heat exchange between at least three fluids. For example, the ports 01-04 are arranged in a conventional manner. Apart from the skirt S and ports 01 -04 practically the remaining part of the heat exchanger plates 1 10, 120 forms a heat exchanging surface 130, 140. Alternatively, at least a central main portion of the heat exchanger plates 110, 120 between the port openings 01-04 forms the heat exchanging surface 130, 140.
[0043] In the illustrated embodiment, the heat exchanger 100 also comprises a start plate 150 and an end plate 160. The start plate 150 is formed with openings corresponding to the port openings 01-04 for letting fluids into and out of the interplate flow channels formed by the first and second heat exchanger plates 110, 120. The start plate 150 may be provided with port connections 170 for connecting pipes to the heat exchanger 100 for fluids to exchange heat. For example, the start plate 150 is a conventional start plate 150. The end plate 160 is a plate without openings in the illustrated embodiment. Alternatively, the end plate 160 has inlet and / or outlet openings for fluids. For example, the end plate 160 is a conventional end plate.
[0044] With reference to Fig. 2 the first heat exchanger plate 1 10 and the second heat exchanger plate 120 of the heat exchanger 100 are illustrated more in detail. The heat exchanger plates 110, 120 are, e.g., made from sheet metal, such as steel, aluminum, copper or other suitable metals or alloys depending on the use of the heat exchanger. Each heat exchanger plate 1 10, 120 extends in a general plane and has a first face and an opposite second face, wherein the first and second faces or main portions thereof form the heat exchanging surfaces 130, 140.
[0045] Each of the heat exchanger plates 110, 120 is provided with a pressed pattern of ridges R and grooves G. For example, the ridges R extend from the plane of the heat exchanger plates 110, 120 in a first direction, wherein the grooves G extend from said plane in an opposite second direction. The ridges R in one face of the heat exchanger plates 110, 120 form the grooves G of the opposite face thereof. In the illustrated embodiments, the ridges R and groove G are formed in a herringbone pattern as chevrons. Optionally said chevrons are formed with a single apex, wherein the single apex optionally is arranged on a center axis, such as a longitudinal center axis, of the heat exchanger plates 110, 120, i.e. along the middle of the plates. For example, the ridges R and grooves G extend from one side of the heat exchanger plates 1 10, 120 to the opposite side thereof, such as from one long side to the other. Optionally, the ridges R and grooves G extend continuously from one side to the other of the heat exchanger plates 110, 120. As an alternative to the herringbone pattern, the ridges R and grooves G may be in the form of obliquely extending straight lines. In any case, the pressed pattern is adapted to keep the planes of the plates 110, 120 on a distance from one another to form the interplate flow channels. The ridges R and grooves G of the first and second heat exchanger plates 110, 120 are, e.g. arranged in opposite directions.
[0046] For example, the ridges R and grooves G of the first and second heat exchanger plates 1 10, 120 are arranged with the same height and depth throughout the pressed pattern. Hence, all ridges R of the pressed pattern have the same height and all grooves G have the same depth, wherein a press depth of the heat exchanger plates 110, 120 is symmetric and uniform. Alternatively, the first and / or second heat exchanger plate 110, 120 is arranged with ridges R and grooves G with varying height and depth. Hence, the press depth of at least one of the heat exchanger plates 110, 120 is asymmetric and non- uniform. In the embodiment of Figs. 1 and 2, all ridges R of the first heat exchanger plate 110 are formed with the same height and all grooves G are formed with the same depth. Hence, the first heat exchanger plate 1 10 is formed with uniform press depth. The second heat exchanger plate 120, however, is formed with non-uniform press depth, wherein some of the ridges R are formed with a different height than the others. In the illustrated embodiment, every other ridge R of the second heat exchanger plate 120 is formed with a lower height than the neighboring ridges R over most of the heat exchanging area 140. However, other patterns are envisaged. For example every third or fourth ridge R may be formed with a lower height. Alternatively, every third or fourth ridge R may be formed with the taller height. Each of the ridges R has a top portion 180 and each of the grooves G has a bottom portion 190 extending in a longitudinal direction of the ridges R and grooves G. Said top and bottom portions 180, 190 are connected through opposite first and second flanks 200, 210 extending along the ridges R and grooves G. For example, the top and bottom portions 180, 190 extend in a plane parallel to the plane of the heat exchanger plates 1 10, 120. For example, the top and bottom portions 180, 190 are substantially flat. Alternatively, the top and bottom portions 180, 190 are rounded. The first and second flanks 200, 210 have an inclination in relation to the plane of the heat exchanger plates 110, 120. For example, the first and second flanks 200, 210 have an inclination in relation to the tops and bottoms 180, 190. The inclination of at least some of the first flanks 200 and / or the inclination of at least some of the second flanks 210 of the first and / or second heat exchanger plates 110, 120 varies along the ridges R and grooves G. Hence, the inclination is bigger in one portion along the ridge R than in another portion thereof. For example, the inclination is bigger in one end of the ridge R than in an opposite end thereof. Alternatively, the inclination is bigger in a central portion along the ridge R and is smaller at the ends. In addition, or as an alternative to, to the inclination varying along at least some of the ridges and grooves, the inclination of at least some of the first flanks 200 and / or the inclination of at least some of the second flanks 210 of different ridges R and grooves G of the first and / or second heat exchanger plates 110, 120 optionally varies, so that the inclination of one ridge R differs from the inclination of another ridge R. Hence, according to various embodiments the inclination of at least some of the flanks 200, 210 varies between the first and second port openings 01 , 02, i.e. in a general flow direction of the fluid in the interplate flow channel which also may be a longitudinal direction and may be called a Y direction, as well as along the ridges and grooves, i.e. substantially in a lateral direction which also may be called X direction. Hence, at least some of the ridges R have a first flank 200 with a varying inclination profile along the ridge R, wherein the inclination profile of one ridge R may differ from the inclination profile of another ridge R. Optionally, at least some of the ridges R also have a second flank 200 with a varying inclination profile along the ridge R, wherein the inclination profile of one ridge R may differ from the inclination profile of another ridge R. The inclination of at least some of the flanks 200, 210 varies in the X direction and / or the Y direction.
[0047] The first flank 200 of the first heat exchange plates 110 is substantially facing the first port opening 01, wherein the second flanks 210 thereof are substantially facing away from the first port opening 01, so that the fluid hits the first flank 200 of a ridge R before passing its top portion 180 and coming into contact with the second flank 210 of the same ridge R. Hence, the second flanks 210 are substantially facing the second port opening 02. The first flanks 200 of the first heat exchange plates 110 are substantially facing the general fluid flow direction of the first heat exchange fluid in the first interplate flow channels. Hence, when the first port opening 01 is used as the inlet for the first heat exchange fluid, the first heat exchange fluid hits the first flank 200 of a ridge R before passing its top portion 180 and comes into contact with the second flank 210 of the same ridge R.
[0048] In the embodiment of Figs. 1 and 2, the inclination of the first flanks 200 of the first heat exchanger plates 1 10 varies along at least some of the ridges R and grooves G. The inclination of the first flanks 200 varies at least along the ridges R and grooves G in the vicinity of the first port opening 01, wherein the inclination is bigger closer to the first port opening 01 than more remotely from the first port opening 01. The inclination of the first flanks 200 of the first heat exchanger plates 1 10 varies along at least some of the ridges R and grooves G, so that the inclination of the first flanks 200 is bigger in a first longitudinal section of the ridge R closer to the first port opening 01 than in a second longitudinal section thereof more remote from the first port opening. For example, the first longitudinal section is on one side of the longitudinal center axis of the heat exchanger plates 110, 120 and the second longitudinal section is on the other side of said center axis. The inclination of the first flanks 200 of at least some of the ridges R of the first heat exchanger pate 110 decreases from one end to the opposite end along the ridges R. Hence, said inclination decreases generally in the lateral direction from one lateral side of the heat exchanging surface 130 between the first and second port openings 01, 02 to the other lateral side between the third and fourth port openings 03, 04. Hence, the inclination of said first flanks 200 decreases from the first longitudinal section to the second longitudinal section of the ridges R and grooves G. For example, said inclination decreases from one long side of the heat exchanger plate 110 to the opposite long side thereof, optionally continuously along the ridges R and grooves G from one end to the opposite end thereof.
[0049] The inclination of the first flanks 200 of the first heat exchanger plate 110 varies also between at least some of the ridges R and grooves G in a direction between the first and second port openings 01 , 02, i.e. in the longitudinal direction of the heat exchanger plate 110. Hence, the inclination of the first flank 200 of one ridge R differs from the inclination of the first flank 200 of another ridge R. The ridges R closer to the first port opening 01 are formed with a bigger inclination of the first flank 200 than ridges R more remote from the first port openings 01 and closer to the second port opening 02, at least in the first longitudinal section of the ridges R. Hence, the inclination of said first flanks 200 of different ridges R and grooves G decreases in a direction from the first port opening 01 to the second port opening 02.
[0050] In the embodiment of Figs. 1 and 2 also the inclination of at least some of the second flanks 210 of the first heat exchange plate 110 varies both along the ridges R and grooves G and between different ridges R and grooves G. In the embodiment of Figs. 1 and 2, the inclination of the second flanks 210 decrease along the ridges R and grooves G and between different ridges R and grooves G as described for the first flanks 200. Hence, a width of the top portions 180 of the ridges R varies along the ridges R and also between different ridges R, wherein the width of the top portions 180 is bigger in the first longitudinal section of the ridges R closer to the first port opening 01 than in a second longitudinal section thereof more remote from the first port opening 01 . In addition, the width of the top portion 180 of ridges R closer to the first port opening 01 is bigger than the top portion 180 of ridges R more remote from the first port opening 01 in a direction toward the second port opening 02. Hence, the width of the top portion 180 of different ridges R is decreasing in a direction from the first port opening 01 to the second port opening 02.
[0051] In the embodiment of Figs. 1 and 2 the inclination of at least some of the first flanks 200 differs from the inclination of the second flank 210 of the same ridges R and grooves G, at least along a part thereof. Hence, the flanks on opposite sides of a ridge R have different angles at least along a part of said ridge R. For example, the first flank 200 of some of the first longitudinal sections has a bigger inclination than the second flank 210 of the same first longitudinal section. Alternatively, the inclination of the first flank 200 is bigger than the inclination of the second flank 210 throughout the ridge R. For example, the first flank 200 of the ridges R closer to the first port opening O1 has bigger inclination than the second flank 210.
[0052] In the embodiment of Figs. 1 and 2 the second heat exchange plate 120 is formed with first and second ridges Rl, R2, wherein the first ridges R1 are formed with a first height and the second ridges R2 are formed with a second height different from the first height. Hence, the second ridges R2 are lower than the first ridges Rl . Thus, the second heat exchanger plate 120 is formed with asymmetric press depth. The inclination of the flanks 201, 211, 202, 212 of the ridges Rl, R2 and grooves G of the second heat exchanger plate 120 is non- varying, i.e. constant, along the ridges Rl, R2 and grooves G. Hence, the width of the top portion 181 of the first ridges Rl is non-varying and thus constant along the first ridges Rl, wherein the width of the top portion 182 of the second ridges R2 is non- varying and thus constant along the second ridges R2. The width of the top portions 182 of the second ridges R2 are bigger than the width of the top portions 181 of the first ridges R 1 .
[0053] With reference to Figs. 3 and 4 the heat exchanger 100 and a part thereof is illustrated according to a second embodiment. In the second embodiment, the first and second heat exchanger plates 110, 120 are different. The first heat exchanger plate 110 is formed with varying inclination of the flanks 200, 210 along the ridges R and grooves G, at least along the first longitudinal section thereof. For example, the inclination of the first flank 200 decreases from a long side of the first heat exchanger plate 110 to the center axis thereof. Also, the inclination of the first flanks 200 varies between different ridges R and grooves G, wherein the inclination of the first flank 200 decreases in a general flow direction from the first port opening 01 to the second port opening 02. Hence, the inclination of the first flank 200 is bigger in ridges R closer to the first port opening 01 and is smaller in ridges R closer to the second port opening 02. Also, the width of the top portions 180 varies along the ridges R and varies between different ridges R, so that the width of the top portions 180 is bigger closer to the first port opening 01 than the second port opening 02. The inclination of the flanks 200, 210 of at least some of the ridges R and grooves G varies along the ridges R and grooves G as described above.
[0054] In the second embodiment, the second heat exchanger plate 120 is arranged as described with reference to the first embodiment, i.e. with the first and second ridges Rl, R2 of different heights. The inclination of the first and second flanks 200, 210 is constant along each ridge Rl, R2 and groove G. Alternatively, the inclination of the first and / or second flank 200, 210 of one or more of the first and / or second ridges Rl, R2 varies along the ridge Rl , R2. Optionally, the inclination of the first and / or second flank 200, 210 of one or more of the first and / or second ridges Rl, R2 varies between different ridges Rl, R2.
[0055] With reference to Figs. 5 and 6 the heat exchanger 100 and a part thereof is illustrated according to a third embodiment, wherein both the first and second heat exchanger plates 110, 120 are formed with varying inclination of the flanks 200, 210 of the ridges R and grooves G. The first heat exchanger plate 110 of the third embodiment corresponds to the one described with reference to the second embodiment. In the third embodiment, the second heat exchanger plate 120 is arranged in a corresponding way as the first heat exchanger plate 110 but with the pattern of ridges and grooves G pointing in the opposite direction. Hence, the second heat exchanger plate 120 has a symmetric press depth, wherein all of the ridges R are of the same height. The second heat exchanger plate 120 is formed with varying inclination of the flanks 200, 210, so that different ridges R and grooves G have different inclination of the flanks 200, 210. For example, the inclination of the flanks 200, 210 decreases in a longitudinal direction of the heat exchanger plate 120 in a direction from the first and fourth port openings 01, 04 to the second and third port openings 02, 03. Optionally, the inclination of the flanks 200, 210 varies also along the ridges R and grooves G of the second heat exchanger plate 120. With reference to Fig. 7 the first heat exchanger plate 110 of the heat exchanger 100 is illustrated according to a fourth embodiment. It is understood that the first and / or second heat exchanger plate 110, 120 can be arranged according to the fourth embodiment. Fig. 7 is a front view illustrating the center axis C of the heat exchanger plate 110. For example, the heat exchanger plates 110, 120 are rectangular, wherein the center axis C is a longitudinal center axis. The first and second port openings O1 , 02 for the first fluid is arranged on one side of the center axis C, wherein the third and fourth port openings 03, 04 are arranged on the other side of the center axis C. Hence, the inlet and outlet for the first fluid is on one side of the center axis C, wherein the inlet and outlet for the second fluid is arranged on the other side. Alternatively, the flow is diagonal, wherein the inlet and outlet are arranged on opposite sides of the center axis C.
[0056] According to the fourth embodiment, the inclination of at least some of the first and second flanks 200, 210 is decreasing along the ridges R and grooves G in a direction away from the first port opening 01. The inclination of said first and second flanks 200, 210 is decreasing along the ridges R and grooves G, optionally continuously, from one long side of the heat exchanger plate 110 to the other. At the same time, the inclination of different flanks 200, 210 is also decreasing in a direction from the first port opening 01 to the second port opening 02 in the longitudinal direction, at least in the vicinity of the first port opening 01 and at least in the same side of the center axis C as the first port opening 01. Hence, the first flank 200 of one ridge R closer to the first port opening 01 has a bigger, i.e. more steep, inclination than the first flank 200 of another ridge R further away from the first port opening 01 . In the illustrated embodiment, also the width of the top portions 180 is bigger in the vicinity of the first port opening 01 and is decreasing further away from the same. Hence, a volume in the interplate flow channel is smaller closer to the first port opening than further away from it, such as in the vicinity of the second port opening 02 and / or the third port opening 03 and / or the fourth port opening 04. In a center portion and / or a portion between the center portion and the second and third port openings 02, 03, the flanks 200, 210 may be formed with constant inclination along the ridges R and grooves G, i.e. non-varying inclination and constant angle in said direction. Optionally, the press depth is symmetric.
[0057] With reference to Fig. 8 the first heat exchanger plate 110 of the heat exchanger 100 is illustrated according to a fifth embodiment. It is understood that the first and / or second heat exchanger plate 110, 120 can be arranged according to the fifth embodiment. In the fifth embodiment, the inclination of at least the first flanks 200 and optionally also the second flanks 210 decreases along at least some of the ridges R and grooves G as described above. In addition, the inclination of at least the first flanks 200 and optionally also the second flanks 210 of one or more of the ridges R at the first port opening 01 is bigger than the inclination of ridges R more remote from the first port opening 01 . In the fifth embodiment, the inclination from one of the first flanks 200 to the next decreases in the direction from the first port opening Of to the second port opening 02 in the side of the center axis of the heat exchanger plate 110 including both the first and second port openings 01, 02, wherein the inclination of at least some of the first flanks 200 in the other side of the cent reline increases in a direction from the fourth port opening 04 to the third port opening 03. Hence, while the inclination of the first flanks 200 decreases in one side of the heat exchanger plate 110 it increases in the other side in the longitudinal direction. For example, a plurality of ridges and groove G in the vicinity of the fourth port opening 04 is formed with a smaller inclination than at least some of the ridges R and groove G more remote from the fourth port opening 04 in the same side of the center axis of the heat exchanger plate 110.
[0058] With reference to Fig. 9 the first heat exchanger plate 110 of the heat exchanger 100 is illustrated according to a sixth embodiment. It is understood that the first and / or second heat exchanger plate 110, 120 can be arranged according to the sixth embodiment. In the sixth embodiment, the inclination of the first flanks 210 is decreasing in one side of the center axis C as described with reference to the fifth embodiment, i.e. decreasing from one ridge R to the next in a direction from the first to the second port openings 01, 02 and also in the longitudinal direction of the ridges R and grooves G. The inclination of the first and second flanks 200, 210 are not the same for the same ridge R. Hence, for the same ridge R the first flank 200 is different from the second flank 210 at least for some of the ridges R and grooves G. In addition, on the side of the center axis including the third and fourth port openings 03, 04, the width of the top portions 180 varies between different ridges R. In the illustrated embodiment, a plurality of ridges R at the fourth port opening 04 and at the third port opening is formed with a smaller width than in a central portion of the heat exchanger plate 110. Hence, the inclination of the first and / or second flanks 200, 210, and optionally the width of the top portions 180, of the first and / or second heat exchanger plates 1 10, 120 may vary both along the ridges R and grooves G and also from one ridge R to the next.
[0059] With reference to Figs 10 and 11, the first heat exchanger plate 110 is illustrated schematically in different sections according to one embodiment, wherein the inclination of the first flanks 200 varies along the ridges. Hence, a first ridge R1 has a first angle al of inclination in a first section, as illustrated in Fig. 10 and a second angle a2 of inclination in a second section. The angle of inclination is relative the plane of the heat exchanger plate 110. For example, the first section is on one side of the center axis, such as the longitudinal center axis, of the heat exchanger plate 1 10, wherein the second section is in the other side of said center axis. For example, the first and second sections are substantially in the general flow direction, illustrated by the arrow Y in Figs. 10 and 11. For example, the first section is between the first and second port openings 01, 02 and the second section is between the third and fourth port openings 03, 04 of the heat exchanger plate 110. The first angle al is different from the second angle a2. In the illustrated embodiment, the first angle al is bigger than the second angle a2. A second ridge R2, being arranged more remote from the first port opening 01 than the first ridge R1 and e.g. neighboring the first ridge R1 , has a third angle a3 of inclination in the first section and a fourth angle a4 of inclination in the second section. The third angle a3 may be different from the fourth angle a4 or may be the same. In the illustrated embodiment, the third angle a3 is bigger than the fourth angle a4. For example, the difference between the third and fourth angles a3, a4 is different from the difference between the first and second angles al, a2. Hence, the first and second ridges Rl, R2 have different inclination profiles. Further, a third ridge R3, e.g. more remote from the first port opening 01 than the second ridge R2, has a fifth angle a5 of inclination in the first section and a sixth angle a6 of inclination in the second section. The fifth angle a5 may be different from the sixth angle a6 or may be the same. In the illustrated embodiment, the fifth angle a5 is smaller than the sixth angle a6. For example, the difference between the fifth and sixth angles a5, a6 is different from the difference between the third and fourth angles a3, a4. Hence, the first to third ridges R1-R3 have different inclination profiles. In the illustrated embodiment, the first to third ridges Rl- R3 are directly neighboring each other. However it is understood that this is optional and that a plurality of ridges with the same inclination profile can be arranged in consecutive order, optionally followed by one or more ridges with a different inclination profile.
[0060] For example, the ridges R1-R3, etc. of the first heat exchanger plate 110 and optionally also of the second heat exchanger plate 120 can be arranged with the same height Hl as illustrated in Figs. 10 and 11. Hence, the tops of the ridges R1-R3 are arranged in the same plane parallel to the plane of the heat exchanger plate 110, 120. Similarly, the bottom of the groove G may also be arranged in the same plane, parallel to the plane of the heat exchanger plate 1 10, 120. Hence, the first heat exchanger plates 110, or both the first and second heat exchanger plates 110, 120, of the heat exchanger 100 may be symmetric in the sense that basically all ridges R1-R3, at least in the heat exchanging surface 130, have the same height, such as a first height Hl. Hence, the top portions of the ridges in the first face of the heat exchanger plate are arranged in a plane parallel to the top portions of the ridges in the second face of the heat exchanger plates.
[0061] With reference to Figs 12 and 13 the second heat exchanger plate 120, and optionally also the first heat exchanger plate 110, is asymmetric in the sense that the ridges R4-R7 in the first face of the heat exchanger plate 120 have different heights H2, H3. Some of said ridges R5, R7 have a second height H2, wherein others R4, R6 have a third height H3 different from the second height H2. For example, the second height H2 is bigger than the third height H3, wherein only the ridges R5, R7 with the bigger height H2 contacts ridges of an adjacent heat exchanger plate 1 10, 120. The ridges R5, R7 with the bigger height H2 are also called first ridges, wherein the ridges with the lower height H3 also are called second ridges. For example, the top portions of the ridges in the second face of the heat exchanger plates are all arranged in the same plane parallel to the plane of the heat exchanger plate 120. Hence, the bottom of the grooves are all arranged in the same plane. The top portions of the first ridges R5, R7 are arranged in a first common plane, wherein top portions of the second ridges R4, R6 are arranged in a second common plane parallel to the general plane of the heat exchanger plate. The inclination profiles of the ridges R4-R7 may be similar to the inclination profiles described with reference to Figs. 10 and 1 1 , i.e. varying along the ridges R4-R7 as well as between different ridges R4-R7 in a general flow direction Y.
[0062] With reference to Figs. 14-17, the ridges Rl-Rn are formed in a herringbone pattern as chevrons. For example, each chevron has a single apex optionally arranged on the center axis C of the heat exchanger plates 110, 120, such as a longitudinal center axis. For example, the Ridges Rl-Rn extend from one side of the heat exchanger plates 110, 120 to the opposite side thereof, such as from one long side to the other. Optionally, the ridges Rl-Rn extend continuously from one side to the other of the heat exchanger plates 110, 120. Instead of the herringbone patterns, the ridges Rl-Rn may also be in the form of obliquely extending straight lines extending from one side of the heat exchanger plate 110, 120 to the opposite side thereof. In any case, the ridges, i.e. at least the ridges with bigger height, are adapted to keep the planes of the plates 110, 120 on a distance from one another to form the interplate flow channels.
[0063] With reference to Fig. 14, the first heat exchanger plate 1 10 is illustrated schematically. The ridges Rl-Rn of the first heat exchanger plates 110 are formed with uniform height, wherein the first heat exchanger plates 110 are symmetric in respect of corrugation depth. The first heat exchanger plates 110 are formed with the ridges Rl-Rn in a first chevron angle 01 . The chevron angle is the angle between legs of the same ridge connected in the apex. The legs of the ridge are inclined and extend from the apex towards opposite sides of the heat exchanger plate 110, 120, such as the long sides thereof. Optionally, the ridges and grooves of the first heat exchanger plates 110, and optionally also the second heat exchanger plates 120, are formed with the first chevron angle 01 throughout the heat exchanging area 130, 140 of the plate. For example, the first chevron angle 01 is 50°-140°, such as 80°-130°. In the case of ridges in the form of straight oblique lines, the ridges are inclined in an angle corresponding to one of the legs of the chevron from one side of the heat exchanger pate to the opposite side, such as half of the chevron angle to the center axis C.
[0064] With reference also to Fig. 15, the second heat exchanger plates 120 may be formed with a second chevron angle (32. Optionally, the second chevron angle (32 is different from the first chevron angle (31. Hence, the second heat exchanger plates 120 are arranged with a herringbone pattern having a different angle than the first heat exchanger plate 1 10. For example, the second chevron angle (32 is 50°-140°, such as 80°-130°. Optionally, the second heat exchanger plates 120 are formed with the second chevron angle (32 throughout the heat exchanging area 140 of the plate. An optional difference between the first and second angles (31, (32 is, e.g. 4-70° or 2-35. In the embodiment of Fig. 15, the ridges Rl-Rn of the second heat exchanger plates 120 are formed with uniform height, wherein the first heat exchanger plates 110 are symmetric in respect of corrugation depth.
[0065] With reference to Fig. 16, the first heat exchanger plate 110 is illustrated schematically, wherein the ridges R4-Rn are formed with different heights, so that the first heat exchanger plates 110 are asymmetric in respect of corrugation depth as described above. The first heat exchanger plates 110 are formed with the ridges Rl-Rn in the first chevron angle (31 as described above. With reference also to Fig. 17, the second heat exchanger plates 120 may be formed with the second chevron angle (32 and varying corrugation depth, wherein the ridges are formed with different heights as described above. The heat exchanger 100 may comprise different combinations of the first and second heat exchanger plates 110, 120 having ridges with varying flank inclination, including first and second heat exchanger plates 1 10, 120 with uniform corrugation depth (symmetric / symmetric), optionally with different chevron angles, first heat exchanger plates 110 with uniform corrugation depth and second heat exchanger plates with varying corrugation depth (symmetric / asymmetric) or vice versa (asymmetric / symmetric), optionally with different chevron angles, or first and second heat exchanger plates 110, 120 with varying corrugation depths (asymmetric / asymmetric), optionally with different chevron angles. In addition the inclination of the flanks are varying along the ridges and / or between different ridges.
Claims
CLAIMS1. A plate heat exchanger (100) comprising a plurality of first and second heat exchanger plates (110, 120) having a center axis (C), at least first, second, third and fourth port openings (O1-O4) and a pattern of elongated and alternating ridges (R) and grooves (G) providing contact points between at least some crossing ridges (R) and grooves (G) of adjacent heat exchanger plates (1 10, 120) under formation of interplate flow channels for fluids to exchange heat, wherein the interplate flow channels are in selective fluid communication through the port openings (O1-O4), wherein each of the ridges (R) has a top portion (180) and each of the grooves (G) has a bottom portion (190) extending in a longitudinal direction of the ridges (R) and grooves (G), and wherein said top and bottom portions (180, 190) are connected through opposite first and second flanks (200, 210) extending along the ridges (R) and grooves (G), characterised in that an inclination of the first flank (200) of at least some of the ridges and grooves differs from an inclination of the second flank (210) thereof, and the inclination of said first flank varies along the ridges (R) and grooves (G), and / or between different ridges and grooves.
2. The plate heat exchanger of claim 1, wherein the first port opening (01) is an inlet for a first fluid and the second port opening (02) is an outlet for the first fluid.
3. The plate heat exchanger of claim 1 or 2, wherein the first flanks (200) are facing the first port opening (01) and wherein the second flanks (210) are facing the second port opening (02).
4. The plate heat exchanger of any of the preceding claims, wherein the inclination of said first flanks (200) decreases along the ridges and grooves from one side of the center axis (C) to an opposite second side thereof and in a direction away from the first port opening (01).
5. The plate heat exchanger of any of the preceding claims, wherein the inclination of said first flanks (200) of different ridges and grooves decreases in a direction along said center axis (C) and on a first side of the center axis (C).
6. The plate heat exchanger of claim 5, wherein the inclination of said first flanks (200) of different ridges and grooves increases in a direction along said center axis (C) and on a second side of the center axis (C) opposite the first side thereof.
7. The plate heat exchanger of any of the preceding claims, wherein the inclination of at least some of the second flanks (210) varies along the ridges and grooves.
8. The plate heat exchanger of any of the preceding claims, wherein the inclination of said first flank (200) is bigger than the inclination of said second flank (210) of the same ridges and grooves at least in the vicinity of the first port opening (01).
9. The plate heat exchanger of any of the preceding claims, wherein the inclination of at least some of the second flanks (210) varies between different ridges and grooves.
10. The plate heat exchanger of claim 9, wherein the inclination of said second flanks (210) of different ridges and grooves decreases in a direction from the first port opening to the second port opening.1 1 . The plate heat exchanger of any of the preceding claims, wherein a width of at least some of the top portions (180) varies.
12. The plate heat exchanger according to claim 11, wherein the width of said top portions (180) varies along a longitudinal direction thereof.
13. The plate heat exchanger according to claim 12, wherein the width of said top portions (180) decreases along at least a portion of the longitudinal direction of the ridges.
14. The plate heat exchanger according to claim 13, wherein the width of said top portions (180) decreases in a direction away from the first port opening (01).
15. The plate heat exchanger of any of the preceding claims, wherein the width of at least some of the top portions (180) varies between different ridges.
16. The plate heat exchanger of claim 15, wherein said width decreases between the ridges in a direction from the first port opening (01) to the second port opening (02).
17. The plate heat exchanger of any of the preceding claims, wherein the inclination of at least some of the first flanks (200) varies along the ridges (R) and grooves (G), so that the inclination of the first flanks (200) is bigger closer to the first port opening (01) than more remote from the first port opening (01).
18. The plate heat exchanger of claim 17, wherein the inclination of said first flanks (200) of different ridges and grooves decreases in a direction from the first port opening (01) to the second port opening (02).
19. The plate heat exchanger of claim 17 or 18, wherein the inclination of the first flanks (200) of ridges in the vicinity of the second port opening (02) varies along the ridges (R) and grooves (G), so that the inclination of the first flanks (200) is smaller closer to the second port opening (02) than more remote from the second port opening (02).
20. The plate heat exchanger of any of the preceding claims, wherein the first and second heat exchanger plates are rectangular, wherein the port openings (01-04) are arranged near comers of the heat exchanger plates, wherein the first and second port opening (01) are arranged on a first side of the center axis (C), wherein the third and fourth port openings are arranged on a second side of the center axis (C) opposite the first side, and wherein the inclination of the first flank (200) of at least some of theridges and grooves is bigger than the inclination of the second flank (210) thereof in the vicinity of the first port opening (Ol) on the first side of the center axis (C).
21. The plate heat exchanger of any of the preceding claims, wherein the inclination of the first flanks decreases between ridges and grooves in a direction from the first port opening to the second port opening on the first side of the center axis.
22. The plate heat exchanger of any of the preceding claims, wherein the inclination of the first flanks of the ridges and grooves in the vicinity of the first port opening decreases in a direction from the first side of the center axis to the second side thereof.
23. The plate heat exchanger of any of any of the preceding claims, wherein the inclination of the first flanks of the ridges and grooves in the vicinity of the second port opening increases in a direction from the first side of the center axis to the second side thereof.