Coupling device, kit, and heat transfer arrangement including the same

Abstract

This disclosure relates to a coupling device (300) for fluidly connecting a refrigerant recirculation loop (134) to heat exchanger refrigerant ports (210a, 210b) of a heat exchanger (200) in a heat pump (130a, 130b, 130c), wherein the heat exchanger refrigerant ports (210a, 210b) extend into the heat exchanger (200) from the refrigerant port opening end (212) toward the refrigerant port bottom end (214) and fluidly connect to an internal heat exchange channel (220) of the heat exchanger (200). The coupling device includes a body (310) having an internal conduit line (312) and a filter unit (340). The coupling device (300) is structured and positioned such that when mounted on the heat exchanger (200), the body (310) protrudes into the heat exchanger refrigerant ports (210a, 210b) from the refrigerant port opening end (212) toward the refrigerant port bottom end (214), so that the filter unit (340) is positioned near the bottom end of the refrigerant port.

Description

Technical Field

[0001] Field of Disclosure The present disclosure relates to a coupling device for fluidly connecting a refrigerant recirculation loop to a heat exchanger refrigerant port of a heat exchanger within a heat pump. The present disclosure further relates to a kit including the coupling device and the heat exchanger. The present disclosure further relates to a heat transfer arrangement for heating and / or cooling a building, including the coupling device and / or the kit.

Background Art

[0002] Background Art Nearly all large advanced cities around the world have at least the following two types of energy grids incorporated into their infrastructure; a grid for providing electrical energy and a grid for providing heating and hot water generation. Today, the common grid used to provide heating and hot water generation is a gas grid that provides combustible gas (usually fossil fuel gas). The gas provided by the gas grid is burned locally to provide heating and hot water. There are plans to replace such gas grids with “green” energy efficient energy systems in order to reduce carbon dioxide emissions.

[0003] One such energy efficient energy system is a cold thermal grid. A cold thermal grid is an evolution of district heating systems and district cooling systems, where a combined district heating and district cooling system assisted by the use of heat pumps for heating and cooling can provide both heating and cooling and hot water generation to buildings.

[0004] For a successful gas grid replacement (each gas burner being replaced by a heat pump), the heat pumps used must be smaller, less expensive, easier to control, and have lower technical complexity (e.g., having fewer and / or less complex sensors to measure ambient heat and tap water energy consumption than the heat pumps currently in use). A refrigerant is required in the heat pump, and the heat pump's high efficiency (COP) depends on the efficient refrigerant. Many efficient refrigerants have a high GWP (Global Warming Potential), and consequently there is an incentive to use refrigerants with a low GWP. Some refrigerants have a low GWP but have other undesirable characteristics that have led authorities to set requirements for the maximum amount of GWP allowed in a single heat pump, in order to be permitted to be placed in certain zones, such as uncultivated areas within a building. A small amount of refrigerant will inevitably limit the COP, and this will inevitably limit the maximum power of the heat pump. One example of such a refrigerant is R290, and the currently permissible amount of R290 in a heat pump is 152g when placed in an unventilated area.

[0005] Therefore, there is a need for technologies that make heat pumps more efficient (particularly regarding the use of refrigerants) in order to provide adequate heating within the limits set by the authorities. [Overview of the project] [Problems that the invention aims to solve]

[0006] overview The object of the present invention is to mitigate, reduce, or eliminate one or more of the defects and disadvantages identified above in the art, either individually or in any combination. These and other objects are at least partially satisfied by the present invention as defined in the independent claims. Preferred embodiments are described in the dependent claims. [Means for solving the problem]

[0007] According to the first embodiment, a coupling device is provided for fluidly connecting a refrigerant recirculation loop to a heat exchanger refrigerant port of a heat exchanger in a heat pump, wherein the heat exchanger refrigerant port extends into the heat exchanger from the opening end of the refrigerant port toward the bottom end of the refrigerant port and is fluidly connected to an internal heat exchange channel of the heat exchanger, and the coupling device is The main body includes an inner conduit line having a constant cross-sectional area when viewed in a transverse direction with respect to the refrigerant flow direction, and the main body is A mounting portion structured and positioned to be attachable to a heat exchanger at the opening end of a refrigerant port, the mounting portion having a connection port for connecting to a fluid conduit system of a refrigerant recirculation loop, the connection port being in fluid communication with an internal conduit line; and A distribution section having an elongated extension from the first end that connects to a mounting section and a second end opposite the first end, the inner conduit line includes a distribution section that opens at the second end, The coupling device further includes a filter unit positioned at the second end of the distribution section in such a manner that the refrigerant passing through the inner conduit line is filtered through the filter unit, When the coupling device is mounted on the heat exchanger, it is structured and positioned such that the filter unit is located near the bottom end of the refrigerant port, and the distribution section protrudes into the heat exchanger refrigerant port from the opening end of the refrigerant port toward the bottom end of the refrigerant port, such that a flow path interconnecting the internal conduit lines of the coupling device with the internal heat exchange channels of the heat exchanger is defined between the outer wall of the distribution section and the inner wall of the heat exchanger refrigerant port.

[0008] The coupling device according to the first embodiment may be advantageous because it allows for a reduction in the amount of refrigerant that does not contribute to heat transfer in the refrigerant recirculation loop of a heat pump for various reasons. This is achieved by means of reducing unnecessary volume in the fluid conduit system housing the refrigerant recirculation loop. By minimizing such unnecessary volume, the total amount of refrigerant in the system can be reduced. Furthermore, much of this unnecessary volume is shaped so that refrigerant does not accumulate there and thereby never contribute to the heat transfer process.

[0009] The parts of the refrigerant recirculation loop that are particularly vulnerable to this problem are the inlets and / or outlets of the heat exchangers. A heat pump has two heat exchangers that act simultaneously as an evaporator and a condenser, respectively. The refrigerant must pass through both of these heat exchangers during the refrigerant cycle. This means that the refrigerant must enter and exit twice, thereby creating four passages collectively through the inlets and outlets of the heat exchangers. The reason these passages are particularly vulnerable to the aforementioned problem is that heat exchangers typically have relatively large inlet and outlet port volumes. Here, the refrigerant (especially in passages where it is in liquid form) can accumulate due to wake and turbulence, and thus does not actively contribute to the heat transfer process within the heat pump.

[0010] The coupling device may be advantageous because its shape actively reduces this problem by reducing the volume of the heat exchanger port. By allowing the distribution section to protrude into the heat exchanger refrigerant port, the effective volume of the heat exchanger refrigerant port available to the refrigerant can be significantly reduced. The internal conduit lines of the coupling device can be designed to be relatively narrow and without a constant cross-sectional area when viewed transversely to the refrigerant flow direction, and the risk of refrigerant accumulation within the coupling device may be virtually zero. Leaving the coupling device, the refrigerant enters a flow path formed between the outer wall of the distribution section and the inner wall of the heat exchanger refrigerant port. This flow path interconnects the internal conduit lines of the coupling device with the internal heat exchange channels of the heat exchanger. By design selection, the volume and shape of this flow path can be chosen to further reduce the risk of any refrigerant accumulation. Nevertheless, if any refrigerant does accumulate, the amount of such refrigerant is expected to be significantly reduced compared to conventional solutions as a result of the significantly reduced effective volume of the heat exchanger refrigerant port, as described in detail above.

[0011] Another advantage of the coupled device is that it includes a filter unit. In conventional systems, filtration is typically performed in a separate filtration device connected in series with the refrigerant recirculation loop. Because the filter unit can accommodate a filter, such as a mesh filter, with an active area large enough to provide an acceptable pressure loss within the refrigerant recirculation loop, it also typically defines an unnecessarily large internal volume, which tends to create further volume in the refrigerant recirculation loop where refrigerant can accumulate and therefore does not contribute to heat transfer. By installing the filter unit at the second end of the distribution section, the refrigerant flowing through the internal conduit lines of the distribution section is allowed to pass through the filter unit in the heat exchanger refrigerant port on its way to the internal heat exchange channels of the heat exchanger (where heat transfer consequently occurs).

[0012] The term "refrigerant recirculation loop" here refers to a closed circuit through which a fixed volume of refrigerant is circulated. The refrigerant recirculation loop includes not only the first and second heat exchanger units but also the compressor and expander. The aforementioned units are connected in series by a fluid conduit system to define the refrigerant recirculation loop. The fluid conduit system includes piping, which is typically made of a metal such as copper.

[0013] According to some embodiments, the distribution section has a cross-sectional area that is 50-90% of the cross-sectional area of ​​the heat exchanger refrigerant port when viewed transversely with respect to the refrigerant flow direction. The distribution section may have a cross-sectional area that is 70-90%, 75-85%, or about 80% of the cross-sectional area of ​​the heat exchanger refrigerant port when viewed transversely with respect to the refrigerant flow direction.

[0014] This may be advantageous because it offers a good compromise between achieving a refrigerant flow with an acceptable pressure drop and a significantly reduced total volume to reduce the degree of stationary passive refrigerant in the refrigerant recirculation loop.

[0015] As used herein, the term “cross-sectional area” should be interpreted as the total cross-sectional area defined by an element or part. Therefore, the cross-sectional area of ​​a hollow cylinder should be interpreted as the area of ​​the circle defined by the enveloping surface, rather than the area of ​​the annular ring that can be defined for such a hollow cylinder.

[0016] According to some embodiments, the elongated extension of the distribution section accounts for 70-95% of the longitudinal extension of the flow path.

[0017] This may be advantageous as it offers a good compromise between achieving sufficient space for the filter unit and achieving a significantly reduced total volume to reduce the amount of passive refrigerant in the refrigerant recirculation loop.

[0018] As used herein, the longitudinal extension of the channel is defined parallel to the elongated extension of the distribution section.

[0019] According to some embodiments, the body is integrally formed of one material.

[0020] This may be advantageous as it may facilitate the manufacture of the coupling device. Alternatively, the body may be made of two or more elements that are attached to each other. The body may be made of a metal such as brass, stainless steel, or copper, for example.

[0021] According to some embodiments, the connection port is structured and arranged to accommodate the piping of the fluid conduit system of the refrigerant recirculation loop, and the cross-sectional area of the connection port is larger than the cross-sectional area of the inner conduit line.

[0022] This makes it possible to provide a relatively uniform transition between the piping and the inner conduit line, which may be advantageous as it further helps to minimize the risk of creating stagnant or passive refrigerant within the refrigerant recirculation loop.

[0023] According to some embodiments, the attachment portion has a threaded portion structured and arranged to be threadedly engagable with a related threaded portion of the heat exchanger when attaching the coupling device.

[0024] This may be advantageous as it provides an efficient and secure attachment between the coupling device and the heat exchanger, and further allows for easier replacement of the coupling device. However, other attachment means are also conceivable. Alternatively, the attachment may be achieved by soldering or gluing. For such an attachment, the attachment portion may not have a threaded portion.

[0025] According to some embodiments, the filter unit includes a mesh filter.

[0026] According to some embodiments, the coupling device has a cylindrical geometry. The heat exchanger refrigerant port may be shaped substantially cylindrically. This means that the flow path formed between the outer wall of the distribution portion and the inner wall of the heat exchanger refrigerant port may substantially have the shape of a hollow cylinder. However, other shapes are conceivable.

[0027] According to some embodiments, the coupling device further includes an expansion valve directly attached to the attachment portion. The expansion valve can be an electronic expansion valve or a thermostatic expansion valve. The expansion valve can be attached to the attachment portion by soldering.

[0028] This may be advantageous as it allows for further reduction of the unnecessary volume within the fluid conduit system of the refrigerant recirculation loop. Further, this may simplify the assembly of a heat pump including such a coupling device.

[0029] According to a second aspect, a kit for a heat pump is provided that includes: a heat exchanger including first and second heat exchanger refrigerant ports for fluidly connecting the heat exchanger to a refrigerant recirculation loop of a heat pump, wherein each of the first and second heat exchanger refrigerant ports extends into the heat exchanger from its respective heat exchanger port open end towards its respective heat exchanger port bottom end and is fluidly connected to an internal heat exchange channel of the heat exchanger, and a coupling device according to any one of the preceding claims structured and arranged such that when attached onto the heat exchanger at one of the first and second heat exchanger refrigerant ports, a filter unit is disposed near the heat exchanger port bottom end so as to project into said one of the first and second heat exchanger refrigerant ports from its respective heat exchanger port open end towards its respective heat exchanger port bottom end, and a flow path interconnecting an inner conduit line of the coupling device and the internal heat exchange channel of the heat exchanger is defined between an outer wall of the distribution portion and an inner wall of the heat exchanger refrigerant port.

[0030] According to a third aspect, a heat transfer arrangement for heating and / or cooling a building is provided that includes at least one heat pump including at least one coupling device according to the first aspect and / or at least one kit according to the second aspect.

[0031] According to several embodiments, at least one heat pump is at least one modular liquid / liquid heat pump, and each of the at least one modular liquid / liquid heat pumps is structured and arranged to be individually detachable from the heat transfer arrangement.

[0032] According to several embodiments, at least one modular liquid / liquid heat pump is multiple modular liquid / liquid heat pumps operating in parallel.

[0033] According to several embodiments, the total amount of refrigerant contained in each of at least one module liquid / liquid heat pumps is less than 400g, less than 300g, or less than 200g.

[0034] The permissible amount of refrigerant in a refrigerant recirculation loop with refrigerant R290 is currently 152g for one type of heat pump, without the requirement that the zone be a ventilated area. The permissible amount of refrigerant in a refrigerant recirculation loop with refrigerant R290 is currently 334g for another type of heat pump, without the requirement that the zone be a ventilated area. Other refrigerants may have various predetermined thresholds.

[0035] The refrigerant can be selected from the group consisting of R290, R32, R410A, R470C, and R134A.

[0036] The effects and features of the second and third embodiments are very similar to those described above in relation to the first embodiment. Several embodiments described for the first embodiment are very interchangeable with the second and third embodiments. It should be further noted that the concept of the present invention relates to all combinations of features unless otherwise explicitly stated.

[0037] Further scope of applicability of this disclosure will become apparent from the detailed description given below. However, it should be understood that the detailed description and specific examples are given only as examples, while they point to preferred embodiments of this disclosure, as various changes and modifications within the scope of this disclosure will become apparent to those skilled in the art from this detailed description.

[0038] Accordingly, it will be understood that this disclosure is not limited to specific components of the described device or steps of the described method (since such devices and methods may change). It will also be understood that the technical terms used herein are for the purpose of describing only specific embodiments and are therefore not intended to be limiting. It should be noted that the singular indefinite and definite articles used herein and in the appended claims mean that there is one or more elements unless the context clearly indicates otherwise. Thus, for example, a reference to “unit” or “the above unit” may include several devices, etc. Furthermore, the word “including” and similar usages do not exclude other elements or steps.

[0039] Brief explanation of the drawing This disclosure will be described in more detail, for example, with reference to the accompanying schematic drawings illustrating currently preferred embodiments of this disclosure. [Brief explanation of the drawing]

[0040] [Figure 1A] This disclosure shows an exemplary embodiment of a modular liquid / liquid heat transfer arrangement for heating and / or cooling and / or supplying tap water to a building, etc. [Figure 1B] Figure 1A shows the module liquid / liquid heat transfer configuration with one of the heat pump modules separated from the above arrangement. [Figure 2A] A heat exchanger according to an exemplary embodiment of the present disclosure is shown in a perspective exploded view. [Figure 2B] Figure 2A shows the heat exchanger when the components are bundled together. [Figure 3]Figures 2A and 2B show the heat exchangers when connected to a refrigerant recirculation loop according to conventional technology. [Figure 4] Figures 2A and 2B show the heat exchanger when connected to a refrigerant recirculation loop by a coupling device according to one embodiment of the present disclosure. [Figure 5A] Figure 4 is a perspective view of the coupling device. [Figure 5B] Figure 4 is a side view of the coupling device. [Figure 5C] This is a cross-sectional view of the coupling device along the section taken along the line X1-X1 in Figure 5B. [Figure 5D] This is a cross-sectional view of the coupling device in Figure 5A along the section taken along the line X2-X2 in Figure 5C. [Figure 5E] This is a cross-sectional view of the coupling device in Figure 5A along the section taken along the line X3-X3 in Figure 5C. [Figure 6A] This is a side view of a coupling device according to another exemplary embodiment of the present disclosure. [Figure 6B] This is a cross-sectional view of the coupling device in Figure 6A along the section taken along the line X4-X4 in Figure 6A. [Modes for carrying out the invention]

[0041] Detailed explanation Next, the Disclosure will be more fully described below with reference to the accompanying drawings illustrating current preferred embodiments of the Disclosure. However, the Disclosure may be embodied in various forms and should not be considered as being limited to the embodiments described herein, rather these embodiments are provided for consistency and completeness and thus fully convey the scope of the Disclosure to those skilled in the art.

[0042] Figures 1 and 2 show, as an example, a modular liquid / liquid heat transfer arrangement 100 for heating and / or cooling and / or supplying tap water to buildings, etc. Hereafter, the modular liquid / liquid heat transfer arrangement 100 may also be referred to as "heat transfer arrangement 100" or "arrangement 100".

[0043] The heat transfer configuration 100 includes a cold side and a hot side. The heat transfer configuration 100 is configured to transfer thermal energy from the cold side to the hot side. The cold side includes first inlet and outlet coupling pipes 111, 112. The cold side is connected to the cold liquid side 101 via the first inlet and outlet coupling pipes 111, 112, thereby forming a cold side liquid recirculation path 103. The hot side includes second inlet and outlet coupling pipes 122, 121. The hot side is connected to the hot liquid side 102 via the second inlet and outlet coupling pipes 122, 121, thereby forming a hot side liquid recirculation path 104.

[0044] The first inlet coupling pipe 111 is configured to supply the cold side liquid (often called brine) from the cold liquid side 101 to the heat transfer arrangement 100. The first outlet coupling pipe 112 is configured to return the cold side liquid from the heat transfer arrangement 100 to the cold liquid side 101, thereby forming a cold side liquid recirculation path 103. During heating, the cold side liquid has a higher temperature when supplied to the heat transfer arrangement 100 and then returned from there to the cold liquid side 101.

[0045] The second outlet coupling pipe 121 is configured to supply the hot side liquid (usually water) from the heat transfer arrangement 100 to the hot liquid side 102. The second inlet coupling pipe 122 is configured to return the hot side liquid from the hot liquid side 102 to the heat transfer arrangement 100, thereby forming a hot side recirculation path 104. During heating, the hot side liquid has a lower temperature when it is supplied to the heat transfer arrangement 100 and then returned from there to the hot liquid side 101.

[0046] The liquid / liquid heat transfer arrangement 100 may be a liquid / liquid heat pump arrangement configured to provide heat to the hot side liquid for heating. The liquid / liquid heat transfer arrangement 100 may be a liquid / liquid cooling pump arrangement configured to remove heat from the cold side liquid for cooling.

[0047] With regard to a typical heating application of configuration 100, the cold liquid side 101 could be an evolved version of a district heating and cooling system, where a district heating and cooling system combined with the assistance of using a heat pump for heating and cooling can provide both heating and cooling and water supply to the building. The cold liquid side 101 can be coupled to a downhole heat exchanger or a borehole heat exchanger. With regard to a typical heating application of configuration 100, the hot liquid side 102 could be a heating system such as a radiator or water supply system within the building. The hot liquid side 102 will be described in detail later.

[0048] The heat transfer configuration 100 further includes three heat pump modules 130a, 130b, and 130c. However, it should be noted that, although not shown, the heat transfer configuration 100 may include fewer than three heat pump modules 130a, 130b, and 130c or more than three heat pump modules 130a, 130b, and 130c. Each heat pump module 130a, 130b, and 130c includes first inlet and outlet ports 131a, 131b, and second inlet and outlet ports 132b, 132a. The first inlet and outlet ports 131a, 131b are connected to first inlet and outlet coupling pipes 111, 112, respectively. The second inlet and outlet ports 132b, 132a are connected to second inlet and outlet coupling pipes 122, 121, respectively.

[0049] When the heat transfer configuration 100 is in use, the three heat pump modules 130a, 130b, and 130c are connected in parallel to one another. This is achieved by first inlet and outlet ports 131a and 131b, which are connected to first inlet and outlet connectors 111 and 112, respectively, and by second inlet and outlet ports 132a and 132b, which are connected to second inlet and outlet connectors 122 and 121, respectively.

[0050] Each heat pump module 130a, 130b, and 130c further includes a refrigerant recirculation loop 134. The refrigerant recirculation loop 134 includes not only the first heat exchanger unit 135 and the second heat exchanger unit 137, but also a compressor 136 and an expander 138. The aforementioned units 135, 136, 137, and 138 are connected in series with each other by a fluid conduit system 133 to define the refrigerant recirculation loop 134. The fluid conduit system 133 includes piping 139, 139' (see Figures 3 and 4). Piping 139, 139' is typically made of a metal such as copper. The expander 134 may be an expansion valve such as an electronic expansion valve or a thermal expansion valve. Such exemplary embodiments will be described further later. The first heat exchanger unit 135 is fluid-connected to first inlet and outlet ports 131a and 131b. Therefore, the first heat exchanger 135 is connected to the first inlet coupling pipe and outlet coupling pipes 111 and 112 via the first inlet port and outlet ports 131a and 131b, respectively. The second heat exchanger unit 137 is fluidly connected to the second inlet port and outlet ports 132b and 132a. Therefore, the second heat exchanger unit 137 is connected to the second inlet coupling pipe and outlet coupling pipes 122 and 121 via the second inlet port and outlet ports 132b and 132a, respectively.

[0051] The refrigerant circulation loop 134 circulates the refrigerant through a first heat exchanger unit 135, a compressor 136, a second heat exchanger unit 137, and an expander 138. In the first heat exchanger unit 135, the refrigerant, which is mainly in the liquid phase at this time, and the cold-side liquid are configured to exchange thermal energy with each other such that as the temperature of the refrigerant increases, the refrigerant evaporates into the gas phase, and this lowers the temperature of the cold-side liquid. Therefore, the first heat exchanger unit 135 is often referred to as the "evaporator." The refrigerant is circulated from the first heat exchanger unit 135 through its heat exchanger refrigerant port 110b to the compressor 136, which is configured to increase the pressure and thereby increase the temperature of the refrigerant before supplying the refrigerant to the second heat exchanger unit 137 through its heat exchanger refrigerant port 110d. In the second heat exchanger unit 137, the refrigerant, which is still in the gas phase, and the hot-side liquid are configured to exchange thermal energy between them so that the temperature of the refrigerant decreases, and the refrigerant condenses into the liquid phase by transferring heat to the hot-side first liquid, thereby increasing the temperature of the hot-side first liquid. Thus, the second heat exchanger unit 137 is often referred to as the "condenser". Next, the refrigerant is circulated from the second heat exchanger unit 137 through its heat exchanger refrigerant port 110c to an expander 138 configured to reduce the pressure of the refrigerant. As the pressure drops, the refrigerant begins to evaporate, and the heat of vapor is taken away from the refrigerant itself, lowering its temperature, and the result is a low-temperature, low-pressure mixture of liquid and vapor, which is then circulated into the first heat exchanger unit 135 through its heat exchanger refrigerant port 110a, and this cycle is started many times.

[0052] As will be readily apparent to those skilled in the art, the refrigerant cycle can be reversed such that the refrigerant recirculation loop 134 flows counterclockwise instead of clockwise in Figure 1A. The option to reverse the refrigerant cycle allows the heat pump to be used to both cool and heat a particular area. To enable the reversal of the refrigerant cycle, a valve mechanism (not shown) is required that allows switching of the input and output to the compressor 136. Such valve mechanisms are well known in the art and will not be further described herein.

[0053] It should be noted that, although not shown, arrangement 100 may include one or more sensors such as a temperature sensor and / or a pressure sensor, one or more control valves such as a check valve, and one or more flow controllers such as a pump. However, since this is also well known in the art, it is excluded from the attached drawings in this context.

[0054] In addition to what has been discussed in relation to Figure 1A, and as best shown in Figure 1B, each of the heat pump modules 130a, 130b, and 130c may be detachable from the arrangement 100, as they are detachably arranged or placed in a different manner within the arrangement 100. Accordingly, as shown in Figure 1B, it is possible to detach the heat pump module 130c from the first inlet and outlet couplings 111, 112 and the second inlet and outlet couplings 122, 121, so that the heat pump module 130c can be removed from the arrangement 100. In this way, the heat pump module 130c can be removed or replaced as needed. Although not shown in Figure 1B, all of the heat pump modules 130a, 130b, and 130c in this arrangement may be detachably arranged within the arrangement 100, or may be detachable from the arrangement 100. At least one modular liquid / liquid heat pump 130a, 130b, 130c may be multiple modular liquid / liquid heat pumps 130a, 130b, 130c operating in parallel.

[0055] Figures 2A and 2B show a heat exchanger 200 according to an exemplary embodiment of the present disclosure. The heat exchanger 200 is suitable for use in the previously described heat transfer arrangement 100 within each of the heat pump modules 130a, 130b, and 130c. Specifically, any one of the first heat exchanger unit 135 and the second heat exchanger unit 137 may be the heat exchanger 200. The heat exchanger 200 includes a first heat exchanger refrigerant port 210a and a second heat exchanger refrigerant port 210b for fluid connection of the heat exchanger 200 to the refrigerant recirculation loop 134 of the heat pumps 130a, 130b, and 130c. Each of the first heat exchanger refrigerant port and the second heat exchanger refrigerant ports 210a and 210b extends into the heat exchanger 200 from their respective heat exchanger port opening ends 212 toward their respective heat exchanger port bottom ends 214, and is fluidly connected to the internal heat exchange channels 220 of the heat exchanger 200. This is schematically shown in Figure 2B and in more detail in Figures 3 and 4.

[0056] The heat exchanger 200 is of a type often referred to as a plate heat exchanger and is constructed of multiple plate members 202a, 202b that are stacked on top of each other and then sealed together (usually by brazing between adjacent plate members 202a, 202b or by installing sealing members such as gaskets). Each plate member 202a, 202b has four port holes 204 and a surface shape pattern 250 which is optionally provided, for example, by a corrugated shape. Fluid channels 220, 221 are formed between each plate member 202a and adjacent plate members 202b. Heat channels 220, 221 are provided in an alternative way when the multiple plate members 202a, 202b are assembled by designing the plate members 202a differently from the plate members 202b and stacking them in an alternative way, or by designing the gaskets differently and providing these gaskets in an alternative way. The heat channel 220 formed in this manner will enable fluid communication between the heat exchanger refrigerant port 210a and the heat exchanger refrigerant port 210b. In the same manner, the heat channel 221 formed in this manner will enable fluid communication between the heat exchanger secondary fluid port 215a and the heat exchanger secondary fluid port 215b. The heat exchanger includes external connectors 230a, 230b for connecting the heat exchanger 200 to the refrigerant recirculation loop 134 and external connectors 235a, 235b for connecting the heat exchanger 200 to a secondary fluid (e.g., brine on the cold side or water on the hot side). The fluid motion within the heat exchanger 200 is schematically shown in Figure 2A, where the solid black line shows the motion of the secondary fluid through the internal heat exchange channel 221, and the dotted line shows the motion of the refrigerant through the internal heat exchange channel 220. As will be readily apparent to those skilled in the art, the stacked assembly described above will result in a plurality of superimposed port holes 204 at each corner of the heat exchanger 200. The overlapping port holes 204 define the shapes of the heat exchanger ports, such as the heat exchanger refrigerant ports 210a and 210b.

[0057] It should be understood that the heat exchanger 200 is provided herein as just one example among many of the heat exchangers provided herein. There are many more alternative exemplary embodiments of heat exchangers than those described with reference to Figures 2A and 2B, which may have heat exchanger refrigerant ports 210a, 210b that extend into the heat exchanger from a refrigerant port opening end 212 toward a refrigerant port bottom end 214 and are fluidly connected to an internal heat exchange channel 220, and the coupling devices provided herein are equally applicable to any such alternative exemplary embodiments of heat exchangers.

[0058] A problem associated with heat exchangers such as the heat exchanger 200 in Figures 2A and 2B is that the total volume of the heat exchanger refrigerant ports 210a and 210b tends to be very large due to structural constraints in the manufacturing of the heat exchanger 200. As seen in Figure 2B, the heat exchanger refrigerant ports 210a and 210b may extend from one side of the heat exchanger to the other opposite side. Furthermore, the diameter of the port holes 204 may be very large (typically 1.5 to 5 cm). The relatively large volume of the heat exchanger refrigerant ports 210a and 210b risks creating unnecessary volume in the fluid conduit system, which defines the refrigerant recirculation loop 134 and therefore requires a larger total weight of refrigerant to completely fill the fluid conduit system 133 of the refrigerant recirculation loop 134. Moreover, the unnecessary volume can be shaped in such a way that refrigerant tends to accumulate there and therefore never effectively contributes to the heat transfer process. This is particularly problematic, as a narrower portion of the fluid conduit system in the refrigerant recirculation loop 134 opens up to a wider / larger volume.

[0059] To better understand this problem, Figure 3 shows the heat exchanger refrigerant port 210a of a heat exchanger 200 connected to a conventional refrigerant recirculation loop 134' (only a portion of the refrigerant recirculation loop 134' is shown in Figure 3). The refrigerant first passes through a filter unit 340' to remove unwanted materials such as particles by a mesh filter 342'. As clearly shown in Figure 3, the conventional filter unit 340' has a significantly larger cross-sectional area than the piping 139' used to transport the refrigerant to the filter unit 140' when viewed transversely with respect to the refrigerant flow direction L. Apart from generating an unnecessarily large total volume of the fluid conduit system 133' that defines the refrigerant recirculation loop 134', the conventional filter unit 340' also defines a pocket where the refrigerant can accumulate, thus providing a pocket of static refrigerant that never contributes to the heat transfer process. This is schematically shown in Figure 3 by a static refrigerant pocket 30. Downstream of the filter unit 340', the refrigerant recirculation loop 134' includes piping 139' that connects to the heat exchanger refrigerant port 210a of the heat exchanger 200 via an external connector 230a. Similarly, the significantly larger cross-sectional area of ​​the heat exchanger refrigerant port 210a, viewed transversely to the refrigerant flow direction, from piping 139' used to carry the refrigerant, creates yet another pocket of static refrigerant 32 at the bottom of the flow path 350' (defined in the prior art as the total volume of the heat exchanger refrigerant port 210a). Note that areas 30 and 32 in Figure 3 are intended to mark the volumes of static refrigerant. The white areas above areas 30 and 32 are also filled with refrigerant, but this volume of refrigerant mainly flows through the system as indicated by the arrows and therefore never accumulates. In a typical refrigerant recirculation loop of a heat pump filled with R290 as the refrigerant, this static and therefore passive refrigerant can be 15-20 grams, which can account for at most 10-15% of the total mass of refrigerant in the recirculation loop. The highest percentage is typically encountered with respect to a heat pump or heat pump module positioned in an unventilated area where the allowable amount of R290 is currently 152 g.

[0060] To mitigate this problem, a coupling device is provided. This coupling device will be described in detail with reference to Figures 4 and 5E-5A, which show one exemplary embodiment: coupling device 300.

[0061] The coupling device 300 is provided here to fluidly connect the refrigerant recirculation loop of the heat pump to the heat exchanger refrigerant port of the heat exchanger. In this exemplary embodiment, the coupling device 300 is used to connect the refrigerant recirculation loop 134 to the heat exchanger refrigerant port 210a of the heat exchanger 200 in any one of the heat pumps 130a, 130b, and 130c. As previously stated, the heat exchanger refrigerant port 210a extends into the heat exchanger 200 from the refrigerant port opening end 212 toward the refrigerant port bottom end 214 and fluidly connects to the internal heat exchange channel 220 of the heat exchanger 200.

[0062] The coupling device 300 includes a body 310 having an inner conduit line 312. The inner conduit line 312 has a constant cross-sectional area A1 (see Figure 5D) when viewed transversely with respect to the refrigerant flow direction L. Preferably, the constant cross-sectional area A1 of the inner conduit line 312 is close to or equal to the cross-sectional area of ​​the piping 139 (see Figure 4). The coupling device 200 preferably has a cylindrical geometry. In exemplary embodiments, the body 310 is integrally formed from a single material. The body 310 may be made of a metal such as steel, brass, stainless steel, or copper.

[0063] The main body 310 includes a mounting portion 320 structured and positioned to be attached to the heat exchanger 200 at the refrigerant port opening end 212. As shown in Figure 4, the mounting portion 320 is in an exemplary embodiment that attaches to an external connector 230a of the heat exchanger refrigerant port 210a. This mounting portion can be implemented in many alternative ways. In a non-limiting example, this mounting portion can be implemented by a screw engagement, as in the exemplary embodiments shown in Figures 4 and 5A-5E. To achieve this objective, the mounting portion 320 has a screw portion 324 (see Figures 5A and 5B) structured and positioned to screw engage with the associated screw portion 213 (see Figure 4) of the heat exchanger 200 when attaching the coupling device 200. The mounting portion 230 further has a connection port 322 for connecting to the fluid conduit system 133 of the refrigerant recirculation loop 134. The connection port 322 is in fluid communication with the internal conduit line 312. The connection port 322 is structured and positioned to accommodate the piping 139 of the fluid conduit system 133 of the refrigerant recirculation loop 134. The cross-sectional area A4 of the connection port 322 (see Figure 5E) is preferably larger than the cross-sectional area A1 of the inner conduit line 312. In a preferred embodiment, the cross-sectional area A4 of the connection port 322 is dimensioned such that the cross-sectional area A1 of the inner conduit line 312 matches the cross-sectional area of ​​the piping 139 (see Figure 4). The connection port 322 may be provided by drilling. By providing a connection port 322 having a diameter slightly larger than the diameter of the piping 139, the piping 139 can be attached to the connection port 322 by soldering in a manner known to those skilled in the art.

[0064] The main body 310 further includes a distribution section 330 having an elongated extension E1 from a first end 331 that connects to a mounting section 320, and a second end 332 opposite the first end 331. The inner conduit line 312 opens at the second end 332. The coupling device 200 further includes a filter unit 340 positioned at the second end 332 of the distribution section 330 in such a manner that the refrigerant passing through the inner conduit line 312 is filtered through the filter unit 340. The filter unit 340 includes a mesh filter 342 (and optionally a mounting means 341). The mounting means 341, in an exemplary embodiment, is an external ring 341 that is pressed onto the main body 310 to mount the mesh filter 342 onto the main body 310. However, the mesh filter 341 may also be mounted by welding, preferably by laser welding or soldering. As seen in Figures 4 and 5A-5C, the filter unit 340 is positioned such that the mesh filter 342 is substantially coaxial with the coupling device 300 and the inner conduit line 312. This ensures that all refrigerant leaving the inner conduit line 312 is filtered by the filter unit 340. The heat exchanger refrigerant port 210a can be shaped substantially cylindrical. This suggests that the flow path formed between the outer wall 333 of the distribution section 330 and the inner wall 211 of the heat exchanger refrigerant port 210a may substantially have the shape of a hollow cylinder. However, other shapes are possible.

[0065] As best shown in Figures 4 and 5C, the coupling device 300 is structured and positioned such that when mounted on the heat exchanger 200, the filter unit 340 is positioned near the bottom end 214 of the refrigerant port, with the distribution unit 330 projecting into the heat exchanger refrigerant port 210a from the refrigerant port opening end 212 toward the bottom end 214 of the refrigerant port. This forms a flow path 350 that interconnects the internal conduit line 312 of the coupling device with the internal heat exchange channel 200 of the heat exchanger 200. The flow path 350 is defined between the outer wall 333 of the distribution unit 330 and the inner wall 211 of the heat exchanger refrigerant port 210a. As is evident when comparing the prior art solution in Figure 3 with the proposed new solution in Figure 4, the flow path 350 has a significantly smaller effective volume than the flow path 350' of the prior art solution in Figure 3, since the latter corresponds to (or nearly corresponds to) the entire volume of the heat exchanger refrigerant port 210a. The distribution section 330 may have a cross-sectional area A2 that is 70-90% of the cross-sectional area A3 of the heat exchanger refrigerant port 210a when viewed transversely with respect to the refrigerant flow direction L. The elongated extension E1 of the distribution section 330 may be 70-95% of the longitudinal extension E2 of the flow path 350. As will be readily apparent to those skilled in the art, the details described herein with reference to the heat exchanger refrigerant port 210a are equally applicable to the heat exchanger refrigerant port 210b.

[0066] Figures 6A and 6B show a coupling device 400 according to another exemplary embodiment of the present disclosure. The coupling device 400 is similar to the coupling device 300 already described in detail above, and similar reference numbers refer to similar features, so it will not be described further here. The coupling device 400 differs from the coupling device 300 in that it further includes a mounting portion 420 and an expansion valve 438 which is in a directly mounted state. As seen in Figure 6B, the connection port 422 of the mounting portion 420 is shorter and structured and positioned to accommodate the piping 442. The connection port 422 is fluidly connected to the internal conduit line 412. The expansion valve 438 is an electrically operated expansion valve with respect to the exemplary embodiment, but a thermal expansion valve is also conceivable. The expansion valve 438 is only partially shown in Figures 6A and 6B. Those skilled in the art will be well aware of how an electrically operated expansion valve works, and therefore the expansion valve 438 will only be briefly described herein. The expansion valve 438 includes a valve body 444 attached to piping 442 at its opposite end. A movable shaft 448 is axially positioned within the valve body 444 and is configured to move to control the size of the opening 450 formed between the expansion valve 438 and piping 442. A second pipe 446 is positioned within the valve body 444 to allow the refrigerant to enter the expansion valve 438. In an exemplary embodiment of the form of a steel ring, the expansion valve 438 is directly attached to the mounting section 420 by a mounting structure 440. Mounting may be done by soldering, but other mounting means such as screw mounting are possible. As will be readily understood by those skilled in the art, the coupling device 400 will constitute an integrated component having both the filter and the expansion valve. This can simplify the assembly of the heat pump by reducing the number of individual parts. Furthermore, this can help further reduce unnecessary volume in the fluid conduit system housing the refrigerant recirculation loop. Those skilled in the art will understand that, in relation to a heat pump having two or more coupling devices, only one coupling device having an integrated expansion valve may be required for each refrigerant recirculation loop 134.

[0067] The coupling devices of the present disclosure may be provided together with the heat exchangers of the present disclosure. Thus, for example, coupling device 300 may be provided together with heat exchanger 200. The two entities may be provided as a kit. This is shown in Figure 4, which shows the parts of kit 500, which includes heat exchanger 200 and coupling device 300. In other words, kit 500 includes heat exchanger 200 including first heat exchanger refrigerant ports 210a and second heat exchanger refrigerant ports 210b for fluid connection of heat exchanger 200 to refrigerant recirculation loops 134 of heat pumps 130a, 130b, 130c, wherein each of the first and second heat exchanger refrigerant ports 210a and 210b extends into heat exchanger 200 from their respective heat exchanger port opening ends 212 toward their respective heat exchanger port bottom ends 214 and fluid connection to internal heat exchange channels 220 of heat exchanger 200; and A coupling device 300 according to any one of the prior claims, wherein when mounted on the heat exchanger 200 in one of the first and second heat exchanger refrigerant ports 210a, 210b, the distribution unit 330 is structured and positioned such that a filter unit 340 is positioned near the heat exchanger port bottom end 214 such that it protrudes into one of the first and second heat exchanger refrigerant ports 210a, 210b toward the heat exchanger port bottom end 214 toward the heat exchanger port bottom end 214 toward the heat exchanger port opening end 212 toward the heat exchanger port bottom end 214 toward the heat exchanger port opening end 212 toward the heat exchanger port bottom end 214, and a flow path 350 interconnecting the internal conduit line 312 of the coupling device with the internal heat exchange channel 200 of the heat exchanger 200 is defined between the outer wall 333 of the distribution unit 330 and the inner wall 211 of the heat exchanger refrigerant ports 210a, 210b.

[0068] As will be readily apparent to those skilled in the art, the kit may include any heat exchanger unit and coupling device within the scope of the appended claims. For example, the kit may include a coupling device 400 together with a heat exchanger 200.

[0069] The features of the heat transfer arrangement 100 are further described with reference again to Figures 1A and 1B. As previously stated, the heat transfer arrangement 100 includes at least one heat pump 130a, 130b, 130c, and one or more of the at least one heat pump 130a, 130b, 130c may include at least one coupling device 300 according to the Disclosure. In other words, one or more of the at least one heat pump 130a, 130b, 130c may include at least one kit 500 according to the Disclosure (Figure 4). It is conceivable to provide any one of the heat exchanger refrigerant ports 110a, 110b, 110c, and 110d as coupling devices 300 and 400 according to the Disclosure. However, the coupling device is best positioned on the side where the heat exchanger units 135 and 137 are interconnected via the expander 138 (i.e., on one or more of the heat exchanger refrigerant ports 110a and 110c). This is because the refrigerant is at least partially in the liquid phase on this side of the refrigerant recirculation loop 134, and therefore the benefit of reducing unnecessary volume within the refrigerant recirculation loop 134 is greater than on the other side where the refrigerant is in the gaseous phase.

[0070] The installation of coupling devices 200, 300, or kit 500 may result in the total amount of refrigerant contained in each of at least one module liquid / liquid heat pumps 130a, 130b, and 130c being less than 400g, less than 300g, or less than 200g. This may be beneficial as regulations impose limits on the permissible amount of R290 refrigerant that may be used in a single heat pump. Specifically, the permissible amount of R290 refrigerant that may be used in a refrigerant recirculation loop is currently 152g for one type of heat pump, without the requirement that the zone be a ventilated area. The permissible amount of R290 refrigerant in a refrigerant recirculation loop is currently 334g for another type of heat pump, without the requirement that the zone be a ventilated area. Other refrigerants may have various predetermined thresholds.

[0071] Those skilled in the art will understand that this disclosure is by no means limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. In addition, variations of the disclosed embodiments can be understood and enabled by those skilled in the art when performing the claims from the accompanying drawings, this disclosure, and the accompanying claims.

Claims

1. A coupling device (300, 400) for fluidly connecting a refrigerant recirculation loop (134) to the heat exchanger refrigerant ports (210a, 210b) of a heat exchanger (200) in a heat pump (130a, 130b, 130c), wherein the heat exchanger refrigerant ports (210a, 210b) extend into the heat exchanger (200) from the refrigerant port opening end (212) toward the refrigerant port bottom end (214) and fluidly connect to the internal heat exchange channel (220) of the heat exchanger (200), the coupling device, The system includes a main body (310) having an inner conduit line (312) having a constant cross-sectional area (A1) when viewed transversely with respect to the refrigerant flow direction (L), and the main body (310) is Mounting portions (320, 420) are structured and arranged at the refrigerant port opening end (212) to be attachable to the heat exchanger (200), wherein the mounting portions have connection ports (322, 422) for connecting to the fluid conduit system (133) of the refrigerant recirculation loop (134), and the connection ports (322, 422) are in fluid communication with the inner conduit lines (312, 412), and The distribution section (330) includes a first end (331) connected to the mounting section (320) and a second end (332) opposite the first end (331) having an elongated extension (E1), and the inner conduit lines (312, 412) open at the second end (332), The coupling device further includes the filter unit (340) located at the second end (332) of the distribution unit (330) in such a manner that the refrigerant passing through the inner conduit lines (312, 412) is filtered through the filter unit (340), The coupling devices (300, 400) are structured and arranged such that, when mounted on the heat exchanger (200), the filter unit (340) is positioned near the bottom end (214) of the refrigerant port, and a flow path (350) interconnecting the inner conduit lines (312, 412) of the coupling device and the internal heat exchange channel (220) of the heat exchanger (200) is defined between the outer wall (333) of the distribution unit (330) and the inner wall (211) of the heat exchanger refrigerant ports (210a, 210b), so that the distribution unit (330) protrudes into the heat exchanger refrigerant ports (210a, 210b) from the refrigerant port opening end (212) toward the bottom end (214).

2. The coupling device (300, 400) according to claim 1, wherein the distribution section (330) has a cross-sectional area (A2) that is 50 to 90% of the cross-sectional area (A3) of the heat exchanger refrigerant ports (210a, 210b) when viewed in a transverse direction with respect to the refrigerant flow direction (L).

3. The coupling device (300, 400) according to claim 1 or 2, wherein the elongated extension (E1) of the distribution section (330) is 70 to 95% of the longitudinal extension (E2) of the flow path (350).

4. The coupling device (300, 400) according to any one of claims 1 to 3, wherein the main body (310) is integrally formed from a single material.

5. The coupling device (300, 400) according to any one of claims 1 to 4, wherein the connection ports (322, 422) are structured and arranged to accommodate the piping (139) of the fluid conduit system (133) of the refrigerant recirculation loop (134), and the cross-sectional area (A4) of the connection ports is greater than the cross-sectional area (A1) of the inner conduit line (312).

6. The coupling device (300, 400) according to any one of claims 1 to 5, wherein the mounting portion (320, 420) has a threaded portion (324) that is structured and arranged to be screw-engaged with the associated threaded portion (213) of the heat exchanger (200) when the coupling device is attached.

7. The coupling device (300, 400) according to any one of claims 1 to 6, wherein the filter unit (340) includes a mesh filter (342).

8. The coupling device (300, 400) according to any one of claims 1 to 7, wherein the coupling device has a cylindrical geometry.

9. The coupling device (300) according to any one of claims 1 to 8, further comprising the mounting portion (320) and an expansion valve (438) in a directly attached state.

10. A kit (500) of heat pumps (130a, 130b, 130c) including the following: A heat exchanger (200) including a first heat exchanger refrigerant port (210a) and a second heat exchanger refrigerant port (210b) for fluidly connecting the heat exchanger (200) to a refrigerant recirculation loop (134) of the heat pump (130a, 130b, 130c), wherein each of the first and second heat exchanger refrigerant ports (210a, 210b) extends into the heat exchanger (200) from its respective heat exchanger port opening end (212) toward its respective heat exchanger port bottom end (214) and fluidly connects to an internal heat exchange channel (220) of the heat exchanger (200); and A coupling device (300, 400) according to any one of claims 1 to 9, wherein when mounted on the heat exchanger (200) in one of the first and second heat exchanger refrigerant ports (210a, 210b), the distribution unit (330) protrudes into one of the first and second heat exchanger refrigerant ports (210a, 210b) toward the respective heat exchanger port opening end (212) toward the respective heat exchanger port bottom end (214), the refrigerant port A coupling device (300, 400) is structured and positioned such that the luta unit (340) is positioned near the bottom end (214) of the heat exchanger port, and a flow path (350) interconnecting the inner conduit lines (312, 412) of the coupling device and the internal heat exchange channel (200) of the heat exchanger (200) is defined between the outer wall (333) of the distribution section (330) and the inner wall (211) of the heat exchanger refrigerant port (210a, 210b).

11. A heat transfer arrangement (100) for heating and / or cooling a building, comprising at least one heat pump (130a, 130b, 130c), At least one coupling device (300, 400) according to any one of claims 1 to 9, and / or At least one kit (500) according to claim 10 A heat transfer arrangement (100) including the heat transfer arrangement.

12. The heat transfer arrangement (100) according to claim 11, wherein the at least one heat pump (130a, 130b, 130c) is at least one modular liquid / liquid heat pump (130a, 130b, 130c), and each of the at least one modular liquid / liquid heat pump (130a, 130b, 130c) is structured and arranged to be individually detachable from the heat transfer arrangement (100).

13. The heat transfer arrangement (100) according to claim 12, wherein the at least one modular liquid / liquid heat pump (130a, 130b, 130c) is a plurality of modular liquid / liquid heat pumps (130a, 130b, 130c) operating in parallel.

14. The heat transfer arrangement (100) according to claim 12 or 13, wherein the total amount of refrigerant contained in each of the at least one module liquid / liquid heat pumps (130a, 130b, 130c) is less than 400g, less than 300g, or less than 200g.

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