Plate heat exchanger and heat pump circuit

Abstract

The present invention relates to a plate heat exchanger (10) comprising a permanently joined first heat transfer plate (1') and a second heat transfer plate (1″), each having a first port hole, a second port hole, a third port hole, and a fourth port hole. Between the first plate and the second plate (1', 1″), a first inter-plate space (36) for a first fluid and a second inter-plate space (38) for a second fluid are formed. A third porthole (32) in an adjacent plate (1′, 1″) forms a porthole channel. The first interplate space (36) is positioned to be in fluid communication with the porthole channel. The plate pattern is configured to block fluid flow between the first interplate space (36) and the porthole channel in a direction parallel to the longitudinal axis (LA) of the plate (1′, 1″), and to guide fluid flow between the first interplate space (36) and the porthole channel in a direction perpendicular to the longitudinal axis (LA).

Description

Technical Field

[0001] The present invention relates to a plate heat exchanger and a heat pump circuit.

Background Art

[0002] A plate heat exchanger defines a space between two sets of plates between the heat transfer plates of the plate heat exchanger. During use of the plate heat exchanger, one of the two fluids exchanges heat with the other fluid flowing through the space between one set of alternating plates and then through the space between the other set of alternating plates. In order to use the plate heat exchanger efficiently, ideally, the fluid is distributed throughout the plate spacing from the port channels formed by the port holes of the heat transfer plates.

[0003] In a heat pump circuit, a first fluid in the form of a refrigerant undergoes two phase changes, from a fluid phase to a gas phase in an evaporator and from a gas phase to a fluid phase in a condenser. In the evaporator, a second fluid is cooled by the evaporating refrigerant. In the condenser, a third fluid is heated by the condensing refrigerant.

[0004] One or both of the evaporator and the condenser in the heat pump circuit can be formed by a plate heat exchanger.

[0005] In a plate heat exchanger in which the first fluid undergoes a phase change in the space between a set of plates, the distribution of the first fluid within the associated plate space can be a particular problem.

[0006] U.S. Patent No. 10,907,906 (Patent Document 1) discloses a plate heat exchanger in which a bypass passage and a main passage are provided upstream of the first and second passages between adjacent plates of a first heat transfer plate and a second heat transfer plate. The bypass passage allows the first fluid flowing in from the first fluid inlet or the second fluid flowing in from the second fluid inlet to flow into the inner fins or corrugated heat transfer surface, spreading vertically in a front view and passing through the adjacent holes that are further away from the corresponding holes. The main passage allows the first fluid flowing in from the first fluid inlet port or the second fluid flowing in from the second fluid inlet port to flow directly into the inner fins or corrugated heat transfer surface without passing through the bypass passage. A flat space is formed around the entire circumference between the peripheral walls of each adjacent hole and the inner fins or corrugated heat transfer surface.

[0007] International Publication No. 94 / 14021 (Patent Document 2) discloses an evaporator in the form of a plate heat exchanger for a refrigerant circuit. This plate heat exchanger has a plate assembly that alternately defines and separates flow paths for the flow of a refrigerant and a heat exchange fluid. A row of holes provided in the plate forms inlet and outlet channels for the flow of the refrigerant and the heat exchange fluid into and out of their respective flow paths. A refrigerant distribution tube is arranged in the refrigerant inlet channel. This tube is provided with an outlet opening that guides the refrigerant into the refrigerant passage. Furthermore, so-called blanking members in the shape of a tube with a C-shaped washer or slot block a portion of the openings from the refrigerant inlet channel to each refrigerant passage, restricting the flow of refrigerant from the openings to a predetermined path toward the centerline of the plate, thereby ensuring uniform distribution of the refrigerant. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] U.S. Patent No. 10,907,906 [Patent Document 2] International Publication No. 94 / 14021 [Patent Document 3] International Publication No. 2013 / 144211

[0009] It is advantageous to provide an efficient plate heat exchanger suitable for the use of phase-change fluids. In particular, it is desirable to be able to effectively distribute the heat transfer fluid across the entire width of the heat transfer plate. To better address one or more of these concerns, one or more plate heat exchangers and / or heat pump circuits having the features defined in one or more independent claims are provided.

[0010] According to one aspect of the present invention, a plate heat exchanger is provided, comprising a plate package of permanently joined heat transfer plates. Each of the alternately arranged first heat transfer plates and adjacent second heat transfer plates of the plate package comprises a first end, a central portion, and a second end, which are continuously arranged along the longitudinal axis of each heat transfer plate, the first end being provided with a first port hole and a fourth port hole, the second end being provided with a second port hole and a third port hole, and the central portion comprising a main heat transfer region. The heat transfer plates are provided with a plate pattern of protrusions and recesses. Between the first heat transfer plates and the second heat transfer plates, alternating first inter-plate spaces for a first fluid and second inter-plate spaces for a second fluid are formed. The third port holes of each adjacent heat transfer plate form a port hole channel that penetrates the plate package. The first inter-plate spaces are arranged to communicate with the port hole channels. The plate pattern at the second end is configured to block fluid flow parallel to the longitudinal axis between the first interplate space and the port-hole channel, and to guide fluid flow perpendicular to the longitudinal axis between the first interplate space and the port-hole channel.

[0011] The first interplate space is arranged to communicate fluidly with the port-hole channel formed by the third port-hole, and the plate pattern at the second end is configured to prevent the fluid between the first interplate space and the port-hole channel from flowing parallel to the longitudinal axis, and instead guide the fluid between the first interplate space and the port-hole channel to flow perpendicular to the longitudinal axis. Thus, during use of the plate heat exchanger, at the second end, the first fluid is facilitated to disperse in the width direction of the heat transfer plate, i.e., perpendicular to the longitudinal axis, and toward the second port-hole.

[0012] Therefore, when using a plate heat exchanger, most of the heat transfer surface in the first inter-plate space is used for heat exchange between the first fluid in the first inter-plate space and the second fluid in the second inter-plate space.

[0013] In particular, the first fluid whose phase changes within the plate heat exchanger benefits from the prevention of fluid flow parallel to the longitudinal axis and the induction of fluid flow in the first inter-plate space, which are provided by the configuration of the plate pattern in the second portion of the heat transfer plate as defined herein.

[0014] In this specification, plate heat exchangers may also be referred to as heat exchangers.

[0015] In this specification, heat transfer plates are also referred to as “(plural) plates,” and when used in the singular, they are also referred to as “plates.” In the technical field, heat transfer plates are also referred to as “heat exchanger plates” or “heat exchange plates.”

[0016] Each heat transfer plate has a substantially rectangular shape, with a first end positioned on one short side of the rectangle and a second end positioned on the opposite short side. The longitudinal axis may form a longitudinal centerline extending parallel to the long side of the rectangle between the first and second ends.

[0017] The first and second heat transfer plates may be of different types, that is, the plate patterns of the ridges (recesses) and recesses of the first and second heat transfer plates may be different. For example, the plate patterns may be different at the first and second ends, such as port holes.

[0018] During use, the plate heat exchanger is configured to exchange heat between a first fluid and a second fluid. The first fluid flows through a first set of interplate spaces, and the second fluid flows through a second set of interplate spaces. The first and second fluids flow through the plate package on opposite sides of their respective heat transfer plates. This achieves heat exchange between the first and second fluids. In this specification, the interplate spaces may also be referred to as "inter-spaces."

[0019] During use of the heat exchanger, the first fluid and the second fluid flow in and out of the plate package through porthole channels formed by first, second, third, and fourth portholes at the first and second ends of the heat transfer plate. Here, the porthole channel formed by the first porthole may be referred to as the first porthole channel, the porthole channel formed by the second porthole may be referred to as the second porthole channel, the porthole channel formed by the third porthole may be referred to as the third porthole channel, and the porthole channel formed by the fourth porthole may be referred to as the fourth porthole channel.

[0020] The port hole channel penetrates the plate package perpendicular to the longitudinal axis.

[0021] The first and second interplate spaces are configured to communicate fluidly with a single porthole channel at each of the first and second ends.

[0022] When using a phase-changing first fluid, the port-hole channels formed by the third port-holes form either an outlet or an inlet for the first fluid, depending on whether the plate heat exchanger operates as a condenser or an evaporator. Refrigerants used in heat pump circuits are an example of such a phase-changing first fluid.

[0023] During the use of the plate heat exchanger, heat transfer between the first and second fluids occurs primarily through the main heat transfer region located in the center of the heat transfer plate. However, the first and second ends also contribute to heat transfer between the two fluids. Therefore, the plate pattern presented herein at the second end is configured to prevent fluid flow between the first inter-plate space and the port-hole channel formed by the third port-hole in a direction parallel to the longitudinal axis, and to guide fluid flow between the first inter-plate space and the port-hole channel formed by the third port-hole in a direction perpendicular to the longitudinal axis, thereby contributing to the provision of an overall efficient plate heat exchanger. This is because, since fluid flow between the first inter-plate space and the third port-hole channel is blocked in a direction parallel to the longitudinal axis, the fluid flow is guided toward the second port-hole side of the heat transfer plate. Thus, the region of the heat transfer plate near the second port-hole is reliably utilized for heat exchange between the first and second fluids.

[0024] The directional guidance of the fluid flow between the first interplate space and the port-hole channel, as discussed here, means that the fluid flow is directed perpendicular to the longitudinal axis, or at least has a component perpendicular to the longitudinal axis. That is, when passing through the plate pattern at the second end, which is configured to prevent fluid flow parallel to the longitudinal axis between the first interplate space and the port-hole channel, the fluid flow may also have a component parallel to the longitudinal axis.

[0025] However, the plate pattern at the second end prevents a flow direction that is perfectly parallel to the longitudinal axis.

[0026] The plate pattern can provide a desired flow resistance to the fluid in the first and second sets of spaces between the plates and / or promote turbulence of the fluid in the first and second sets of spaces between the plates, and thus can provide a specific heat transfer capacity of the plate heat exchanger associated with the use of the plate heat exchanger.

[0027] The first space between the plates and the second space between the plates may have the same depth or different depths when viewed perpendicular to the longitudinal axis and parallel to the port hole channels.

[0028] The number, size and shape of the heat transfer plates provide a constant heat exchange capacity for a specific flow rate of the fluid flowing through the heat exchanger.

[0029] In the plate package, the protrusions of the first heat transfer plate abut against the recesses of the adjacent second heat transfer plate, and similarly, the protrusions of the second heat transfer plate abut against the recesses of the adjacent first heat transfer plate. Such abutments between adjacent heat transfer plates can be singular points, for example, in the main heat transfer region. In some parts of the heat transfer plate, the abutment can be linear, for example, when forming the port hole channels around the port hole.

[0030] Along the edges of the first and second heat transfer plates, the first and second heat transfer plates are arranged within a seal abutment for laterally partitioning the space between the plates. For example, the edges may be provided with flanges that overlap each other.

[0031] As described above, in plate packages, heat transfer plates are permanently joined. The joints between heat transfer plates can be formed by a joining method that applies heat lower than the melting point of the heat transfer plate material. Such joining methods may be either brazing by adding a brazing material such as foil, paste, or powder containing copper or nickel, or joining by applying a melt-inhibiting composition to the heat transfer plate before heating and joining with the heat transfer plate material, as described in, for example, International Publication No. 2013 / 144211 (Patent Document 3).

[0032] In this specification, when the direction of flow through the first interplate space is not specified, general descriptions refer to flow into or from the third porthole channel formed by the third porthole. Thus, in general discussions, the porthole channel formed by the third porthole may form the outlet channel for the first fluid in the first interplate space, or the inlet channel for the first fluid in the first interplate space. The same applies to general discussions concerning the second interplate space and the flow of the second fluid in the second porthole channel, i.e., the porthole channel formed by the second porthole.

[0033] In the following, porthole channels may be referred to from time to time. This refers to a porthole channel formed by a third porthole. Other porthole channels are defined by specifically referring to the related portholes, such as the second, third, or fourth portholes that form the related porthole channel.

[0034] According to the embodiment, the plate pattern at the second end of each first heat transfer plate includes a ridge extending from the first heat transfer plate in an adjacent first interplate space of the first set of interplate spaces, the ridge being coupled to an adjacent second heat transfer plate of the second set of heat transfer plates to demarcate a portion of the first interplate space. At least a portion of the ridge extends perpendicular to the longitudinal axis, thereby blocking the fluid flow between the first interplate space and the porthole channel formed by the third porthole in a direction parallel to the longitudinal axis. In this way, during use of the plate heat exchanger, the first fluid flow in the first interplate space can be guided to flow through the intermediate portion of the heat transfer plate between the third porthole and the second porthole into or out of the porthole channel formed by the third porthole.

[0035] According to the embodiment, the inter-plate spaces of the first and second plates may each be partially separated by a first side edge extending substantially parallel to the longitudinal axis and a second side edge extending substantially perpendicular to the longitudinal axis. The respective corners of the first and second heat transfer plates may be formed on the first and second side edges. The respective third port holes of the first and second heat transfer plates may be located at the corners, and the first portion of the ridge may be configured to extend from the first side edge toward the longitudinal axis. This prevents the flow of the first fluid along the first side edge in the third port hole during use of the heat exchanger. Thus, the first fluid in the third port hole is forced to flow through the intermediate portion of the heat transfer plate between the first and second port holes, through the port hole channel formed by the third port hole, or into the port hole channel, i.e., into the intermediate portion of the first plate where heat exchange with the second fluid in the intermediate portion of the second plate becomes more efficient. In other words, the flow rate of the second fluid in the second porthole channel is higher than the flow rate in the first corner formed by the first and second side edges.

[0036] According to the embodiment, the second portion of the ridge may extend from the first portion of the ridge toward the second side edge. In this way, during use of the heat exchanger, the flow of the first fluid in the first interplate space flows toward or toward the second port hole near the second side edge. Thus, the first fluid is forced to flow through the third port hole channel or toward the third port hole channel near the second side edge. Thus, the first fluid flowing into or from the port hole channel formed by the third port hole is guided to flow toward or from the second side edge, while passing through the entirety or at least a large portion of the second port hole. This ensures efficient heat exchange with the second fluid flowing into or from the port hole channel formed by the second port hole.

[0037] According to one embodiment, the second portion of the ridge may terminate at a distance from the second side edge, and a passage between the first interplate space and the porthole channel formed by the third porthole may be formed between the second portion of the ridge and the second side edge. In this way, during use of the heat exchanger, the flow of the first fluid in the first interplate space can be guided through the passage away from the second porthole near the second side edge, or toward the second porthole. Thus, the first fluid is forced to flow through the passage into the porthole channel formed by the third porthole, or out of the porthole channel toward or away from the second porthole near the second side edge. Thus, the first fluid entering and leaving the third porthole channel is guided to flow along the second side edge, passing through the entirety, or at least a large portion, of the second porthole. This ensures efficient heat exchange with the second fluid entering and leaving the second porthole channel.

[0038] According to the embodiment, the length of the passage may be within the range of 0.15 to 0.25 times the circumference of the third porthole. This allows the third fluid to be efficiently guided toward the second side edge in the first interplate space during use of the plate heat exchanger.

[0039] According to one embodiment, the ridge may be positioned adjacent to the port hole channel formed by the third port hole. In this way, the surface portion of the heat transfer plate is prevented from being used for heat exchange between the first and second fluids, or only a minimal portion of the surface is used.

[0040] According to the embodiment, a fluid passage is formed in each second inter-plate space along the ridge of the first heat transfer plate. In this way, during use of the plate heat exchanger, the second fluid is guided through this fluid passage toward or from the first side edge of the heat transfer plate. Thus, the fluid flow of the second fluid throughout the heat transfer plate is promoted. This ensures efficient heat exchange in the heat exchanger.

[0041] According to the embodiment, the first or fourth portholes of adjacent heat transfer plates may form further porthole channels that penetrate the plate package. The plate pattern at the first end may be configured to guide the fluid flow between the further porthole channels and the first interplate space in directions parallel to and perpendicular to the longitudinal axis. In this way, during use of the heat exchanger, the first fluid can be evenly distributed in the first interplate space in the further porthole channels, in the flow from or to the further porthole channels.

[0042] Therefore, the additional porthole channel could be either the first porthole channel or the fourth porthole channel. This depends on whether the first or fourth porthole channel is positioned to have fluid communication with the first interplate space.

[0043] According to one embodiment, each heat transfer plate may comprise a metal sheet shaped to form protrusions and recesses of a plate pattern. In other words, the heat transfer plate can be made from a metal sheet.

[0044] Heat transfer plates can be manufactured by cutting metal sheets. Pressing processes are used to create plate-like protrusions and recesses, and angled flanges are also fabricated as needed.

[0045] A further aspect of the present invention provides a heat pump circuit comprising an expansion device, an evaporator, a compressor, and a condenser, wherein the condenser includes a plate heat exchanger according to any one of the embodiments and / or models discussed herein.

[0046] Further features and advantages of the present invention will become apparent upon consideration of the appended claims and the detailed description below. [Brief explanation of the drawing]

[0047] Various aspects and / or embodiments of the present invention, in particular their specific features and advantages, will be readily apparent from the examples of embodiments described below and in the accompanying drawings.

[0048] [Figure 1a] A plate heat exchanger according to an embodiment is shown. [Figure 1b] A plate heat exchanger according to an embodiment is shown. [Figure 2a] A first heat transfer plate according to an embodiment is shown. [Figure 2b] A first heat transfer plate according to an embodiment is shown. [Figure 3a] A second heat transfer plate according to an embodiment is shown. [Figure 3b] A second heat transfer plate according to an embodiment is shown. [Figure 4a] This shows an embodiment of the heat transfer plate in the plate package of a plate heat exchanger. [Figure 4b] This shows an embodiment of the heat transfer plate in the plate package of a plate heat exchanger. [Figure 4c] This shows an embodiment of the heat transfer plate in the plate package of a plate heat exchanger. [Figure 4d] This shows an embodiment of the heat transfer plate in the plate package of a plate heat exchanger. [Figure 5] A schematic diagram of the heat pump circuit according to this embodiment is shown.

[0049] In Figures 2a to 24c, a portion of the heat transfer plate unrelated to the present invention is masked with a white area. [Modes for carrying out the invention]

[0050] The aspects and / or embodiments of the present invention will be described in more detail below. Throughout the specification, the same reference numerals indicate the same elements. Well-known functions or configurations do not necessarily need to be described in detail for the sake of brevity and / or clarity.

[0051] Figures 1a and 1b show a side view and a top view of the plate heat exchanger 10 according to an embodiment.

[0052] The plate heat exchanger 10 comprises a plurality of heat transfer plates 1 according to any embodiment described herein, a first end plate 2 provided beside the outermost heat transfer plate 1, and a second end plate 3 provided on the opposite side of the outermost heat transfer plate 1. The second end plate 3 is located within the flange 7 of the outermost heat transfer plate 1 and is therefore not shown in Figure 1a. For this reason, the second end plate 3 is shown as a dashed line in Figure 1a. The longitudinal axis LA extends along the longitudinal direction of the plate 1.

[0053] The heat transfer plates 1 are manufactured by forming metal sheets and are arranged adjacent to one another. The first end plate 2, the second end plate 3, and the heat transfer plates 1 are permanently joined to each other. At least the heat transfer plates 1 form a plate package 4. Each heat transfer plate 1 has a flange 7 extending around it. The flanges 7 of adjacent plates 1 overlap and are permanently joined to each other.

[0054] Within the plate package 4, two different types of adjacent heat transfer plates 1 separate a first inter-plate space for a first fluid and a second inter-plate space for a second fluid (see Figures 2a-4d below). The first and second fluids can be any suitable fluids from which heat is transferred during use of the plate heat exchanger 10. However, as described herein, the plate heat exchanger 10 is particularly suitable when the first fluid is a phase-change fluid such as a refrigerant.

[0055] The plate heat exchanger 10 has four port hole channels S1, S2, S3, and S4 formed by port holes formed in each plate 1. The first port hole channel S1 is connected to a connecting pipe 11 and communicates with the first inter-plate space or the second inter-plate space. The second port hole channel S2 is connected to a connecting pipe 12 and communicates with the second inter-plate space. The third port hole channel S3 is connected to a connecting pipe 13 and communicates with the first inter-plate space, and the fourth port hole channel S4 is connected to a connecting pipe 14 and communicates with the first inter-plate space or the second inter-plate space. The first port hole channel S1 and the fourth port hole channel S4 communicate with different spaces in the first inter-plate space and the second inter-plate space.

[0056] Connecting pipes that have fluid communication with porthole channels S1, S2, S3, and S4 may be provided extending from the first end plate 2 and / or from the second end plate 3, as disclosed.

[0057] Figures 2a to 3b show the first heat transfer plate 1' and the second heat transfer plate 1'' of the plate heat exchanger 10 in Figures 1a and 1b.

[0058] Figures 2a and 2b show a first heat transfer plate 1' according to an embodiment. Figure 2a shows a top view of the first plate 1', and Figure 2b shows a perspective view of the first plate 1'. Figures 3a and 3b show a second heat transfer plate 1'' according to an embodiment. Figure 3a shows a top view of the second plate 1'', and Figure 3b shows a perspective view of the second plate 1''.

[0059] The first heat transfer plate 1' and the second heat transfer plate 1'' are similar in many respects, but differ in other respects. The following description relating to Figures 2a to 3b applies to both the first heat transfer plate 1' and the second heat transfer plate 1'' unless otherwise specifically referred to.

[0060] The plate heat exchanger 10 in Figures 1a and 1b is constructed by permanently joining alternating first plates 1' and second plates 1''. In the plate package of the plate heat exchanger, the first heat transfer plate 1' and the second heat transfer plate 1'' form at least the main part of the plate package.

[0061] The heat transfer plates 1', 1'' have a rectangular shape with two long side edges and two short side edges. In the illustrated embodiment, the first side edge 16 is a long side edge and the second side edge 18 is a short side edge. The longitudinal axis LA extends parallel to the first side edge 16 and transversely to the second side edge 18.

[0062] Each heat transfer plate 1', 1'' comprises a first end 20, a central portion 22, and a second end 24, which are arranged continuously along the longitudinal axis LA of the heat transfer plate 1', 1''. The first end 20 is provided with a first port hole 26 and a fourth port hole 28, and the second end 24 is provided with a second port hole 30 and a third port hole 32.

[0063] The central section 22 includes a main heat transfer region 34. The main heat transfer region 34 forms the main area of ​​heat transfer between the first fluid and the second fluid on opposite sides of the first plate 1' and the second plate 1'' during use of the plate heat exchanger.

[0064] The heat transfer plates 1' and 1'' are provided with a plate pattern of protrusions and recesses. This plate pattern is provided not only in the main heat transfer region 34 but also in the first end 20 and the second end 24. The plate pattern may differ between the main heat transfer region 34 and the first end 20 and the second end 24.

[0065] In the illustrated embodiment, in the main heat transfer region 34, and also in parts of the first and second ends 20, 24, the plate pattern is formed by alternating projections in the form of obliquely extending ridges and recesses in the form of obliquely extending grooves. The heat transfer pattern primarily facilitates efficient heat transfer between the first fluid and the second fluid. It can also facilitate the dispersion of the first and second fluids across the entire width of the heat transfer plates 1', 1''. However, the present invention is not limited to any particular type of heat transfer pattern.

[0066] The plate's pattern of protrusions and recesses also includes areas around and near portholes 26–32. These areas are primarily designed to form porthole channels that penetrate the plate package and guide fluid flow around the portholes, although some heat transfer may occur in these areas as well.

[0067] At each of the first end 20 and second end 24, the respective port holes 26-32 are surrounded by port hole regions 35', 35'', as shown in Figures 2b and 3b. The port hole regions 35', 35'' are formed in known ways to alternately abut each other along each port hole channel within the heat exchanger, so as to alternately seal the first heat transfer plates 1', 1'' to one another and to define through-flow channels to the first inter-plate space and the second inter-plate space between the first plate 1' and the second plate 1''.

[0068] More specifically, in each porthole region 35', 35'', the heat transfer plates 1', 1'' are provided with circumferential projections and recesses configured to abut against the corresponding circumferential recesses and projections of adjacent heat transfer plates 1', 1''. Joints extending in the circumferential direction are arranged around the portholes 26-32, and these circumferential projections and recesses abut against each other, thereby sealing the corresponding porthole channels from the alternate interplate spaces between plates 1', 1''. As a result, the corresponding porthole channels open into the alternate interplate spaces between plates 1', 1''.

[0069] The plate pattern extends between the first plane and the second plane. The first and second planes of one plate 1', 1'' are parallel to the longitudinal axis LA and parallel to the first side edge 16 and the second side edge 18 of the plate 1', 1''. In the plate package, with the exception of the two outermost heat transfer plates 1', 1'', the first plane of each plate 1', 1'' is positioned adjacent to the second plane of the adjacent plate 1', 1''. Thus, the upper part of the projection extends into the first plane, and the lower part of the recess extends into the second plane.

[0070] Furthermore, the upper part of the circumferential projections of the porthole regions 35' and 35'' extends into the first plane, and the lower part of the circumferential recesses of the porthole regions 35' and 35'' extends into the second plane.

[0071] In the illustrated embodiment, in the first plate 1', the upper part of the circumferential projection in the port hole region 35' around the first port hole 26 and the second port hole 30 extends into the first plane, and the lower part of the circumferential recess in the port hole region 35'' around the third port hole 32 and the fourth port hole 28 extends into the second plane (see Figure 2b). Conversely, in the second plate 1'', the lower part of the circumferential recess in the port hole region 35' around the first port hole 26 and the second port hole 30 extends into the second plane, and the upper part of the circumferential convex portion in the port hole region 35'' around the third port hole 32 and the fourth port hole 28 extends into the first plane (see Figure 3b). In this way, a circumferential joint around the port holes 26 to 32 can be realized.

[0072] Figures 4a to 4d show embodiments of the three heat transfer plates 1', 1'' of the plate package of the plate heat exchanger 10 described with reference to Figures 1a and 1b. Figure 4a shows a top view of plates 1', 1'', Figure 4b shows a perspective view of the second end 24 of plates 1', 1'', Figure 4c shows a perspective cross section along line CC in Figure 4a, and Figure 4d shows a perspective cross section along line DD in Figure 4a.

[0073] Of the three heat transfer plates 1' and 1'' shown in the diagram, the top plate 1' and bottom plate 1' are the first heat transfer plate 1' as described with reference to Figures 2a and 2b, and the intermediate plate 1'' is the second heat transfer plate 1'' as described with reference to Figures 3a and 3b.

[0074] As described above, the plate package of the plate heat exchanger has two sets of spaces formed between plates 1' and 1''. A first inter-plate space 36 for the first fluid and a second inter-plate space 38 for the second fluid are alternately formed between the first heat transfer plate 1' and the second heat transfer plate 1'. Figures 4b to 4d show one of each of the first inter-plate space 36 and the second inter-plate space 38 in partial view.

[0075] Note that the uppermost first plate 1' defines one of the first interplate spaces 36. Therefore, Figures 4a to 4d show detailed views of the inner delimiting surfaces of the first interplate space 36. The same applies to Figures 2a and 2b. Similarly, since Figures 3a and 3b show the second heat transfer plate 1'', Figures 3a and 3b show detailed views of the inner delimiting surfaces of the second interplate space 38.

[0076] As described above, the port holes in plates 1' and 1'' form port hole channels that penetrate the plate package. The second port holes 30 of adjacent heat transfer plates 1' and 1'' form a second port hole channel S2 that penetrates the plate package, and the third port holes 32 of adjacent heat transfer plates 1' and 1'' form a third port hole channel S3 that penetrates the plate package (see also Figure 1b). The first inter-plate space 36 is configured to be in fluid communication with the third port hole channel S3, and the second inter-plate space 38 is configured to be in fluid communication with the second port hole channel S2.

[0077] The plate pattern of the second end 24 is configured to prevent the fluid flow between the first interplate space 36 and the third port-hole channel S3 from flowing in a direction parallel to the longitudinal axis LA, and to guide the fluid flow between the first interplate space 36 and the third port-hole channel S3 to flow in a direction perpendicular to the longitudinal axis LA.

[0078] In Figures 4a and 4b, the direction parallel to the longitudinal axis LA is indicated by a thick arrow DPar, and the direction perpendicular to the longitudinal axis LA is indicated by a thick arrow DPer.

[0079] Generally, this is achieved by arranging the plate patterns of the first plate 1' and the second plate 1'' such that the protrusions and / or recesses of the plate patterns abut each other at the third port hole 32 of the first inter-plate space 36. This abutment extends linearly from the first side edge 16 of plates 1', 1'' toward the opposite side edge 40 of plates 1', 1'', at least in part. Thus, during use of the plate heat exchanger, the first fluid in the first inter-plate space 36 is forced to flow around the abutment. Due to the extension of the abutment, the first fluid flows at least in part along the second port hole 30 and in the third port hole 32 in a direction perpendicular to the longitudinal axis LA.

[0080] As will be described later with reference to embodiments, this contact portion may have a more sophisticated configuration and function to guide flow, but a contact portion such as the one provided by the ridge 42 described below is still within the scope of the general principles described above.

[0081] The plate pattern of the second end 24 of each first heat transfer plate 1' includes a ridge 42 that extends from the first heat transfer plate 1' in adjacent first inter-plate spaces 36 of the set of first inter-plate spaces 36. The ridge 42 forms one of the protrusions of the plate pattern.

[0082] The ridge 42 is coupled to the adjacent second heat transfer plate 1″ and extends into the first interplate space 36. At least a portion of the ridge 42 extends perpendicular to the longitudinal axis LA, preventing the fluid between the first interplate space 36 and the third porthole channel S3 from flowing in the direction DPar, which is parallel to the longitudinal axis LA.

[0083] In Figures 4a to 4d, the ridge 42 of the upper first heat transfer plate 1' is clearly visible. Figures 4c and 4d show the ridge 42 of the lower first heat transfer plate 1', as well as the contact area between the ridge 42 and the second heat transfer plate 1''. At this contact area, the ridge 42 is joined to the second heat transfer plate 1''.

[0084] Therefore, fluid communication between the first interplate space 36 and the third porthole channel S3 is provided only in the region where the ridge 42 does not extend. Thus, the flow of the first fluid in the first interplate space 36 is guided to pass through the intermediate portion 44 of the heat transfer plates 1', 1'' between the third porthole 30 and the second porthole 30. Thus, during use of the plate heat exchanger, all of the flow of the first fluid must pass through this intermediate portion 44 of the plates 1', 1'', and therefore the first fluid must pass through at least a portion of the second porthole 30.

[0085] The first interplate space 36 and the second interplate space 38 are each partially separated by a first side edge 16 extending substantially parallel to the longitudinal axis LA and a second side edge 18 extending substantially perpendicular to the longitudinal axis LA. The first and second side edges 16, 18 may be the first and second side edges 16, 18 of one of the plates 1', 1'' that separate the associated interplate spaces 36, 38. The respective corner portions 46 of the first heat transfer plate 1' and the second heat transfer plate 1'' are formed at the first and second side edges 16, 18 (see Figure 4a). The corner portions 46 are the corner portions at the second ends 24 of the first heat transfer plate 1' and the second heat transfer plate 1''. The respective third port holes 32 of the first heat transfer plate 1' and the second heat transfer plate 1'' are located at the corner portions 46.

[0086] The first portion 48 of the ridge 42 extends from the first side edge 16 toward the side edge 40 that separates the first interplate space 36 and the second interplate space 38 on the opposite side of the first side edge 16.

[0087] The second portion 50 of the ridge 42 extends from the first portion 48 of the ridge 42 toward the second side edge 18.

[0088] Therefore, the fluid communication between the first interplate space 36 and the third porthole channel S3 is directed near the second side edge 18. Thus, during use of the plate heat exchanger, the first fluid flows through the entirety, or at least a large portion of, the second porthole 30.

[0089] According to the embodiment, the second portion 50 of the ridge 42 terminates at a distance from the second side edge 18, and a passage 52 between the first interplate space 36 and the third porthole channel S3 is formed between the second portion 50 of the ridge 42 and the second side edge 18.

[0090] In Figure 4c, the passage 52 is shown between the lower first plate 1' and the second plate 1''. In Figure 4d, the passage 52 is located on the upper first heat transfer plate 1'.

[0091] In each first interplate space 36, the passage 52 provides the only means of fluid communication between the first interplate space 36 and the third porthole channel S3. During use of the plate heat exchanger, the passage 52 directs the flow of the first fluid in the first interplate space 36 to pass through the entirety, or at least a large portion of, the second porthole 30.

[0092] According to the embodiment, the passage 52 may have a length in the range of 0.15 to 0.25 of the circumference of the third porthole 32. Thus, during use of the plate heat exchanger, the third fluid can be efficiently guided toward the second side edge 18 in the first interplate space 36.

[0093] The length of the passage 52 may be in a direction substantially parallel to the longitudinal axis LA.

[0094] Ridge 52 may be located adjacent to the third porthole channel S3.

[0095] Therefore, the surface portions of plates 1' and 1'' are prevented from being used for heat exchange between the first and second fluids, or only a minimal surface portion is used. For example, the ridge 52 is formed at a certain distance from the third port hole 32 of the first plate 1', leaving enough material of plate 1' to join the first plate 1' and the second plate 1'' circumferentially around the third port hole 32, and preventing entry from the third port hole channel S3 into the second interplate space 38.

[0096] Fluid passages 54 can be formed in each second interplate space 38 along the ridge 52 of the first heat transfer plate 1' (see Figure 4d).

[0097] Therefore, during use of the plate heat exchanger, the second fluid is guided through the fluid passage 54 toward or from the first side edge 16 of the heat transfer plates 1', 1''. Thus, the fluid flow of the second fluid is facilitated across the entire width of the heat transfer plates 1', 1''.

[0098] The first porthole 26 and fourth porthole 28 of adjacent heat transfer plates 1' and 1'' form a first porthole channel S1 and a fourth porthole channel S4 that penetrate the plate package (see Figure 4a). The plate pattern of the first end 20 may be configured to guide the fluid flow between the first porthole channel S1 or the fourth porthole channel S4 and the first interplate space 36 in directions parallel to the longitudinal axis LA and perpendicular to the longitudinal axis LA.

[0099] In the illustrated embodiment, the fourth porthole channel S4 is configured to be in fluid communication with the first interplate space 36. Therefore, in the illustrated embodiment, the plate patterns of the first heat transfer plate 1' and / or the second heat transfer plate 1'' at the first end 20 are configured to guide the fluid flow between the fourth porthole channel S4 and the first interplate space 36 in directions parallel to the longitudinal axis LA and perpendicular to the longitudinal axis LA.

[0100] Therefore, during use of the heat exchanger, the first fluid can be evenly distributed in the first interplate space 36 of the fourth porthole channel S4.

[0101] In another embodiment, plates 1', 1'' may be configured such that a first porthole channel S1 is in fluid communication with a first interplate space 36.

[0102] Generally, a plate heat exchanger 10 can be used for heat transfer between a first fluid in the form of a phase-change fluid, such as a refrigerant used in a heat pump circuit, in a first inter-plate space 36, and a second fluid in a second inter-plate space 38.

[0103] In particular, the plate heat exchanger 10 can form a condenser in the heat pump circuit; see also Figure 5.

[0104] Therefore, during use, the first fluid in the gas phase flows into the first inter-plate space 36 through the porthole channels located at the first ends 20 of plates 1', 1''. In the illustrated embodiment, the first fluid also flows into the first inter-plate space through the fourth porthole channel 28. When the first fluid condenses in the first inter-plate space 36, i.e., undergoes a phase change from gas to liquid, it flows from the first inter-plate space 36 into the third porthole channel S3. Thus, this flow-guiding configuration in plates 1', 1'' and the plate pattern of protrusions and recesses in the third porthole 32 ensure that plates 1', 1'' are also made maximum use in heat transfer with the second fluid at the second porthole 30.

[0105] As the first fluid condenses within the first interplate space 36, the volume of the first fluid decreases, and therefore the flow resistance provided by the relatively small cross-sectional area between the first interplate space 36 and the third porthole 32, such as that provided by the passage 52, does not obstruct the flow of the first fluid through the first interplate space 36.

[0106] Figure 5 schematically shows a heat pump circuit 56 according to an embodiment.

[0107] The heat pump circuit 56 comprises an expansion device 58, an evaporator 60, a compressor 62, and a condenser 64, the condenser 64 being a plate heat exchanger 10 according to any one of the embodiments and / or models described herein.

[0108] The above are illustrative examples of various embodiments, and it should be understood that the present invention is defined solely by the appended claims. Those skilled in the art will understand that the exemplary embodiments may be modified without departing from the scope of the invention as defined by the appended claims, and that different features of the exemplary embodiments may be combined to create embodiments other than those described herein. [Explanation of Symbols]

[0109] 1 Heat transfer plate 1′ First heat transfer plate 1″ Second heat transfer plate 2. First end plate 3. Second end plate 4-plate package 7 Flange 10 Plate heat exchanger 11-14 Connecting pipes 16. First side edge 18. Second side edge 20 First end 22 Central part 24 Second end 26-32 Portholes 34 Main heat transfer region 35 Porthole Area 36. The first interplate space 38. The second interplate space 40 Side Edge 42, 52 Ridge 44 Middle section 46 Corner section 48 Part 1 50 Part 2 52 aisles 54 Fluid passage 56 Heat pump circuit 58 Inflation device 60 Evaporator 62 Compressor 64 Condenser LA Longitudinal axis S1-S4: Porthole Channels 1-4

Claims

1. A plate heat exchanger (10) comprising a plate package (4) of permanently joined heat transfer plates (1', 1"), Each of the alternately arranged first heat transfer plates (1') and adjacent second heat transfer plates (1'') of the plate package (4) comprises a first end (20), a central portion (22), and a second end (24) that are continuously arranged along the longitudinal axis (LA) of each heat transfer plate (1', 1''), the first end (20) being provided with a first port hole (26) and a fourth port hole (28), the second end (24) being provided with a second port hole (30) and a third port hole (32), and the central portion (22) including a main heat transfer region (34). The heat transfer plate (1', 1'') is provided with a plate pattern of protrusions and recesses. A set of first inter-plate spaces (36) for a first fluid and a set of second inter-plate spaces (38) for a second fluid are alternately formed between the first heat transfer plate (1', 1'') and the second heat transfer plate (1', 1''). The third port holes (32) of each of the adjacent heat transfer plates (1', 1'') form a port hole channel (S3) that penetrates the plate package (4). The first interplate space (36) is arranged to be in fluid communication with the port hole channel (S3), Plate heat exchanger (10), wherein the plate pattern of the second end (24) is configured to prevent the fluid flow between the first inter-plate space (36) and the port hole channel (S3) from flowing in a direction parallel to the longitudinal axis (LA), and to guide the fluid flow between the first inter-plate space (36) and the port hole channel (S3) in a direction perpendicular to the longitudinal axis (LA).

2. The plate heat exchanger (10) according to claim 1, wherein the plate pattern of the second end (24) of each of the first heat transfer plates (1') comprises a ridge (42) extending from the first heat transfer plate (1') in adjacent first inter-plate spaces (36) of the set of first inter-plate spaces (36), the ridge (42) being coupled to an adjacent second heat transfer plate (1') to partition a portion of the first inter-plate space (36), at least a portion of the ridge (42) extending perpendicular to the longitudinal axis (LA), and the fluid flow between the first inter-plate space (36) and the port hole channel (S3) formed by the third port hole (32) is obstructed in a direction parallel to the longitudinal axis (LA).

3. Each of the first inter-plate space (36) and the second inter-plate space (38) is partially separated by a first side edge (16) extending substantially parallel to the longitudinal axis (LA) and a second side edge (18) extending substantially perpendicular to the longitudinal axis (LA), and the respective corner portions (46) of the first heat transfer plate (1') and the second heat transfer plate (1'') are shaped by the first side edge (16) and the second side edge (18). The plate heat exchanger (10) according to claim 2, wherein the third port holes (32) of the first heat transfer plate (1') and the second heat transfer plate (1'') are located in the corner portion (46), and the first portion (48) of the ridge (42) extends from the first side edge (16) toward the side edge (40) that separates the first inter-plate space (36) and the second inter-plate space (38) on the opposite side of the first side edge (16).

4. The plate heat exchanger (10) according to claim 3, wherein the second portion (50) of the ridge (42) extends from the first portion (48) of the ridge (42) toward the second side edge (18).

5. The plate heat exchanger (10) according to claim 4, wherein the second portion (50) of the ridge (42) terminates at a distance from the second side edge (18), and a passage (52) between the port hole channel (S3) formed by the first interplate space (36) and the third port hole (32) is formed between the second portion (50) of the ridge (42) and the second side edge (18).

6. The plate heat exchanger (10) according to claim 5, wherein the length of the passage (52) is within the range of 0.15 to 0.25 of the circumference of the third port hole (32).

7. The plate heat exchanger (10) according to any one of claims 2 to 6, wherein the ridge (42) is arranged adjacent to the port hole channel (S3) formed by the third port hole (32).

8. A plate heat exchanger (10) according to any one of claims 2 to 7, wherein a fluid passage (54) is formed in each of the second inter-plate spaces (38) along the ridge (42) of the first heat transfer plate (1').

9. A plate heat exchanger (10) according to any one of claims 1 to 8, wherein the first porthole (26) or fourth porthole (28) of each of the adjacent heat transfer plates (1', 1") forms further porthole channels (S1, S4) that penetrate the plate package (4), and the plate pattern of the first end (20) is configured to guide the fluid flow between the further porthole channels (S1, S4) and the first inter-plate space (36) in a direction parallel to the longitudinal axis (LA) and in a direction perpendicular to the longitudinal axis (LA).

10. Each of the heat transfer plates (1', 1'') comprises a metal sheet molded to form the protrusions and recesses of the plate pattern, the plate heat exchanger (10) according to any one of claims 1 to 9.

11. A heat pump circuit (56) comprising an expansion device (58), an evaporator (60), a compressor (62), and a condenser (64), wherein the condenser (64) comprises a plate heat exchanger (10) according to any one of claims 1 to 10.

Images