Heat exchanger for thermal coupling of two fluids

Abstract

The present invention relates to a heat exchanger comprising an inflow tube defining a tube longitudinal centre axis, a fluid inlet for an inflow of a first fluid flow being provided on the inflow tube and a flat tube adjacent to the fluid inlet in the direction of the tube longitudinal centre axis, the flat tube being spaced apart from each other along the tube longitudinal centre axis and being in communication with the inflow tube such that the first fluid flow is able to flow along a first fluid path extending from the fluid inlet to the flat tube. The flat tube extends away from the inflow tube through a second fluid path for a second fluid flow, whereby the flat tube is able to be flowed through by the first fluid flow and surrounded by the second fluid flow. Furthermore, the heat exchanger comprises a passage aperture able to be flowed through by the first fluid flow and interacting with the heat exchanger fluid, the passage aperture being fluidly connected in series with the flat tube.

Description

Technical Field

[0001] The present invention relates to a heat exchanger for thermal coupling of two fluids as described in claim 1. Background Technology

[0002] This type of heat exchanger is known. It is particularly used in automotive engineering for the thermal coupling of two fluids, enabling the exchange of heat energy between a first and a second fluid. However, popular heat exchangers often exhibit a phenomenon known as "cold spots," which describes a highly uneven temperature distribution across the heat exchanger. This uneven temperature distribution leads to reduced heat exchanger efficiency, which is undesirable. Summary of the Invention

[0003] Therefore, the object of the present invention is to provide an improvement to the heat exchanger or at least another embodiment.

[0004] In this invention, this objective is achieved through the subject matter of independent claim 1. Advantageous embodiments are the subject matter of the dependent claims and the description.

[0005] The basic concept of this invention is to improve the internal distribution of the fluid flowing through the heat exchanger, which is in particular formed by a two-phase refrigerant-oil mixture on the flat tube of the heat exchanger.

[0006] To this end, the present invention proposes a heat exchanger for thermal coupling of two fluids, the heat exchanger being equipped with an inlet pipe defining a longitudinal central axis of the tube and, in effect, an outlet pipe. On the inlet pipe, on the shell side (i.e., particularly on the longitudinal lower shell or on the longitudinal lower shell as will still be described below), is provided a fluid inlet for a first fluid flow (the heat exchanger fluid being, in particular, a two-phase refrigerant-oil mixture) into which the fluid flows, and a plurality of flat tubes adjacent to the fluid inlet in the direction of the longitudinal central axis of the tube. The flat tubes are spaced apart from each other along the longitudinal central axis of the tube. Furthermore, each flat tube communicates with the inlet pipe, allowing the first fluid flow to flow along a first fluid path extending from the fluid inlet through the inlet pipe, the flat tubes (and, if applicable, through the outlet pipe to a further downstream location). The flat tubes extend away from the inlet and outlet pipes through a second fluid path for a second fluid flow (particularly air), allowing the flat tubes to be flowed through by the first fluid flow and surrounded by the second fluid. Specifically, heat can be exchanged between two fluid flows, where the first fluid flow acts as a heat sink and the second fluid flow acts as a heat source, or vice versa. The heat exchanger according to the invention also includes a channel sieve connected in fluid series with the flat tubes, through which the first fluid flow can pass and interact with the heat exchanger fluid. The interaction between the channel sieve and the heat exchanger fluid eliminates or at least reduces swirling currents (actually called vortices) generated in the fluid inlet region when the heat exchanger fluid flows into the inlet tubes. This has the effect of allowing for optimal distribution of the first fluid flow across the flat tubes. The advantage of this is that virtually each flat tube provides the same volumetric or mass flow rate of the liquid and gas phases, thus enabling a relatively uniform temperature distribution across the heat exchanger.

[0007] It is feasible to position the channel screen orifice upstream of the flat tube relative to the first fluid flow. Simultaneously, the channel screen orifice can be connected downstream of the fluid inlet relative to the first fluid flow. This illustrates the preferred location of the channel screen orifice in the first fluid path. Positioning the channel screen orifice at this location achieves optimal reduction of swirl in the heat exchanger fluid. Advantageously, the channel screen orifice can be located within the inlet tube.

[0008] Furthermore, channel screen holes can be provided on a channel screen, which is positioned in the first fluid channel between the fluid inlet and the flat tube. Moreover, it has been recognized within experimental scope that it is advantageous to position the channel screen between the fluid inlet and the first flat tube, which is adjacent to and directly adjacent to the fluid inlet in the direction of the tube's longitudinal central axis, because this allows for an optimal reduction of swirling flow in the heat exchanger fluid and enables the adjustment of the existing gas and liquid phase distribution of the first fluid flow on the flat tube.

[0009] It is feasible to adjust the gap between the channel screen apertures and the first flat tube, which is adjacent to and directly next to the fluid inlet in the direction of the tube's longitudinal central axis, to be 2.0 mm to 9.0 mm, or preferably 3.0 mm to 6.0 mm. Accordingly, providing a channel screen with channel screen apertures can achieve a preferred reduction of swirling flow in the heat exchanger fluid.

[0010] Furthermore, it is feasible to have channel screen holes disposed on a channel screen that at least partially includes a surrounding outer edge, the channel screen being supported itself at least partially in contact with and optionally in a fluid-tight manner on at least one inner circumferential surface of the inflow pipe by said surrounding outer edge. In this way, the channel screen can be fluid-tightly secured to at least one inner circumferential surface within the inflow pipe, where applicable. Here, it is feasible to secure the channel screen to the inflow pipe in the outer edge region, for example, by brazing or welding, or alternatively or additionally by form-fit and / or non-form-fit means.

[0011] Furthermore, it is feasible to include or form reinforcements on the outer edge to strengthen the channel screen against shape changes, wherein the outer edge is implemented with a thickness of 1.4 mm to 3.0 mm. The advantage of doing so is that the channel screen can be made relatively rigid, thus relatively resistant to mechanical deformation. The resulting advantage is that the channel screen can be supplied in large quantities as bulk material during the heat exchanger manufacturing process. This facilitates the manufacturing of the heat exchanger.

[0012] Furthermore, a channel screen is provided on the channel screen, which includes at least one insert lug projecting radially outward relative to the center of the channel screen. This lug is inserted into a lug groove provided on the inflow pipe and complementary to the at least one insert lug, thereby securing the channel screen to the inflow pipe in a form-fit and / or non-form-fit manner. It is feasible to provide two or more individual insert lugs, each engaging with a lug groove provided on the inflow pipe. With this construction, the channel screen can be installed on the inflow pipe relatively easily.

[0013] In this case, an acute angle (preferably less than 90°) can also be defined between every two insert lugs that project radially outward relative to the center of the channel screen.

[0014] It is feasible that at least one insert lug has two lug sides that are oriented in opposite directions and aligned parallel to each other, and a lug front side that connects the two lug sides to each other. Here, the insert lug can be inserted such that when the channel screen is mounted on the inlet pipe, the lug sides can contactively (and, if applicable, with an oversize fit) abut against the inlet pipe. It is feasible that the lug front side can be disposed radially without contact with the center of the channel screen relative to the channel screen, and, if applicable, form a radially protruding protrusion over the inlet pipe.

[0015] It is feasible to implement the inflow pipe as having two parts, the purpose of which is to divide it into a longitudinal lower shell and a longitudinal upper shell along the longitudinal central axis of the pipe, wherein the outer edge of the channel screen is divided into a first circumferential receiving portion for receiving the longitudinal lower shell and a second circumferential receiving portion recessed relative to the first receiving portion for receiving the longitudinal upper shell. The corresponding inflow pipe, especially a circular pipe, can be produced economically and efficiently. With the aid of the first and second receiving portions, the longitudinal lower shell, particularly having a U-shape or C-shape, and the longitudinal upper shell, also particularly having a U-shape or C-shape, can be relatively easily arranged on the channel screen. Here, the term "recessed" can refer to the center of the channel screen, such that the gap between the first receiving portion and the second receiving portion relative to the center of the channel screen is larger. The first and second receiving portions can be complementaryly configured with the longitudinal lower shell and the longitudinal upper shell, respectively. In this respect, it is advantageous for the channel screen to have a substantially circular or circular surface area.

[0016] Alternatively, channel screen orifices may also be provided on the channel screen, which includes or forms at least one flow separation edge that at least partially frames the channel screen orifices. Furthermore, the channel screen orifices define a circular, segmental opening profile, thus allowing for a relatively advantageous reduction of swirling flow in the heat exchanger fluid.

[0017] The channel sieve holes define a circular segmental opening profile, thus the swirling flow in the heat exchanger fluid can still be reduced relatively well.

[0018] Furthermore, the channel screen openings can be positioned on the channel screen defining the screen center, wherein a plane extending parallel to the longitudinal central axis of the tube extends through the screen center and is orthogonally oriented relative to the central axis of the flat tube defined by the flat tube, such that the plane divides the channel screen into a first side away from the flat tube and a second side facing the flat tube. The channel screen openings are preferably positioned on the first side of the channel screen away from the flat tube. This illustrates the preferred position of the channel screen openings on the channel screen.

[0019] Furthermore, channel screen apertures are typically arranged on channel screen apertures that define a particularly flat surface area, wherein the channel area of ​​the channel screen apertures is at least 5% of the surface area. Alternatively or additionally, the channel area of ​​the channel screen apertures can reach up to 50% or more of the surface area. Typically, the channel area of ​​the channel screen apertures reaches a minimum of 5% and a maximum of 25% of the surface area. It is also conceivable that the channel area of ​​the channel screen apertures reaches 25% to 50%, or 25% to 75%, or 25%, 50%, or 75% of the surface area. Thus, a preferred and advantageous ratio between the channel screen apertures through which the flow can pass and the surface area of ​​the channel screen is illustrated.

[0020] In summary, it should be noted that the present invention preferably relates to a heat exchanger comprising an inlet pipe defining a longitudinal central axis of the pipe, wherein the inlet pipe is provided with a fluid inlet for a first fluid flow and a flat tube adjacent to the fluid inlet in the direction of the longitudinal central axis of the pipe, the flat tubes being spaced apart from each other along the longitudinal central axis of the pipe and communicating with the inlet pipe, such that the first fluid flow can flow along a first fluid path extending from the fluid inlet through the flat tubes. The flat tubes extend away from the inlet pipe through a second fluid path for a second fluid flow, thus the flat tubes can be flowed through by the first fluid flow and surrounded by the second fluid. Furthermore, the heat exchanger includes a channel sieve capable of being flowed through by the first fluid flow and interacting with the heat exchanger fluid, the channel sieve being fluidly connected in series with the flat tubes.

[0021] Other important features and advantages of the invention are described in the dependent claims, the drawings, and the related drawings.

[0022] It should be understood that, without departing from the scope of the invention, the above features and the features which will still be explained below can be used not only in the various combinations described, but also in other combinations or individually. Attached Figure Description

[0023] Preferred exemplary embodiments of the present invention are shown in the accompanying drawings and explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical parts.

[0024] As schematically shown in the accompanying drawings,

[0025] Figure 1 A side view of a preferred exemplary embodiment of the heat exchanger is shown.

[0026] Figure 2 It shows Figure 1 A partial cross-sectional view of the portion of the heat exchanger shown in the dashed box.

[0027] Figure 3 It shows Figure 1 The heat exchanger from Figure 2Another partial cross-sectional view viewed in the direction of arrow III, where the heat exchanger is... Figure 2 Divide by the cross-sectional plane III-III shown.

[0028] Figure 4 A front view of a channel sieve with channel screen holes is shown in a heat exchanger according to another exemplary embodiment; and,

[0029] Figure 5 and Figure 6 Front views of a channel sieve with a heat exchanger aperture, according to another exemplary embodiment, are shown. Detailed Implementation

[0030] Figures 1 to 6 A preferred exemplary embodiment of a heat exchanger for thermal coupling of two fluids, generally indicated by reference numeral 1, is shown. Such a heat exchanger 1 is preferably used in motor vehicle applications, but can also be used in the private sector.

[0031] Figure 1 A preferred, highly simplified heat exchanger 1 according to a first exemplary embodiment is shown in a side view. This heat exchanger is not scaled down, allowing the inlet pipe 3 located on the head side and the outlet pipe 34 located on the bottom side to be observed. The inlet pipe 3 and the outlet pipe 34 are fluidly connected together by a plurality of flat tubes 6, 12 (each flat tube is represented by a line). The inlet pipe 3 defines a longitudinal central axis 2 in its main extension direction and is implemented, by way of example only, as having two parts, comprising a longitudinal lower shell 22 and a longitudinal upper shell 23. A fluid inlet 4, implemented as a cylindrical sleeve, is provided in the longitudinal lower shell 22 of the inlet pipe 3 for the inflow of a first fluid flow 5 of heat exchanger fluid. Furthermore, in Figure 1 Notably, following the fluid inlet 4 are multiple flat tubes 6 and 12, which are adjacent to the fluid inlet along the longitudinal central axis 2 of the pipe and spaced apart from each other. The flat tubes 6 and 12 are disposed on the inlet pipe 3 or the longitudinal lower shell 22 of the inlet pipe 3, such that each flat tube 6 and 12 communicates with the inlet pipe 3. Thus, the first fluid flow 5 can flow along a first fluid path 8 extending from the fluid inlet 4 to the inlet pipe 3, the flat tubes 6 and 12, and the outlet pipe 34. Figure 1 The middle part is represented by a dashed line.

[0032] The flat tubes 6 and 12 extend away from the inlet pipe 3 and the outlet pipe 34 through the second fluid path 9 of the second fluid flow 32 used for cooling fluid, allowing the flat tubes 6 and 12 to be flowed through by the first fluid flow 5 and surrounded by the second fluid flow 32. This means that the two fluid flows 5 and 32 intersect. In this way, heat energy can be exchanged between the two fluid flows 5 and 32. It is feasible for the first fluid flow 5 to act as a heat source and the second fluid flow 32 to act as a heat sink, or vice versa.

[0033] about Figure 2 It should be noted that heat exchanger 1 is equipped with a channel screen 11 including adjacent channel screen holes 10, which are in series with the flat tubes 6 and 12 in fluid connection, and a first fluid path 8 extends through the channel screen holes, allowing the first fluid flow 5 to flow through the holes. The channel screen holes 10 interact with the first fluid flow 5 or the heat exchanger fluid, such that swirling in the heat exchanger fluid generated in the fluid inlet 4 region when the heat exchanger fluid flows into the inlet pipe 3 can be eliminated or at least reduced. This has the effect of being able to regulate the optimal distribution of the first fluid flow 5 at the openings of the flat tubes 6 and 12. Furthermore, the channel screen holes 10 exemplarily define channel regions not otherwise specified in the figures.

[0034] The channel screen 11 or channel screen aperture 10 is disposed in the first fluid path 8 between the fluid inlet 4 and the first flat tube 12 of the flat tubes 6, 12, which is adjacent to and directly adjacent to the fluid inlet 4 in the direction of the longitudinal central axis 2 of the tube. As an example only, the gap 13 between the channel screen 11 or channel screen aperture 10 and the first flat tube 12, measured parallel to the longitudinal central axis 2 of the tube, is adjusted. This gap can be from 2.0 mm to 9.0 mm, or preferably from 3.0 mm to 6.0 mm.

[0035] At once Figure 3 Firstly, it should be noted that the channel screen 10 defines or forms a circular segmental opening profile 27. Furthermore, the channel screen 11 has a peripheral outer edge 14, which is divided into a first circumferential receiving portion 24 and a second circumferential receiving portion 25 recessed relative to the first receiving portion 24. In the assembled state of the heat exchanger 1, the longitudinal upper shell 23 supports itself on the second receiving portion 25 by its radially inwardly oriented inner circumferential surface 15, while the longitudinal lower shell 22 supports itself in a fluid-tight manner on the first receiving portion 24 by its also radially inwardly oriented inner circumferential surface 33. Here, the channel screen 11 can be at least substantially fixed in place at the appropriate positions of the longitudinal lower shell 22 and / or the longitudinal upper shell 23, for example, by brazing or welding, or by form-fitting and / or non-form-fitting connections.

[0036] exist Figure 4 In the middle, the outer edge 14 includes or forms a reinforcing channel screen 11 to resist shape changes, and a reinforcing member 16. Therefore, according to... Figure 4 In an exemplary embodiment, the outer edge 14 is at least partially implemented to have a thickness of 1.4 mm to 3.0 mm.

[0037] In addition, Figure 3 and Figure 4 Notably, the channel screen 11 defines a geometric screen center and includes two independent insertion lugs 18 projecting radially outward relative to the screen center 17. The insertion lugs 18 are used to mount and / or secure the channel screen 11 to the inflow pipe 3 in a form-fit and / or non-form-fit manner. For this purpose, the inflow pipe 3 is equipped with two lug slots 19, which are complementary to the two insertion lugs 18 on the longitudinal upper shell 23, each insertion lug 18 capable of being inserted into said lug slot 19. Figure 3 It is noteworthy that when the insert lug 18 is inserted into the corresponding lug groove 19 of the longitudinal upper shell 23, the channel screen 11 is mounted on the inflow pipe 3 at least in a form-fit manner. Here, the two lug sides 20, which are oriented oppositely and aligned parallel to each other, and the lug front side 21 of the corresponding insert lug 18 that connects the two lug sides 20 to each other, generally abut against the lug groove 19 of the longitudinal upper shell 23 in a contact manner (and, if applicable, in a slightly oversized fit manner).

[0038] exist Figure 3 and Figure 4 As can be seen, the channel screen 10 is framed by the flow separation edge 26 formed by the channel screen 11. The flow separation edge 26 generally interacts with the first fluid flow 5 flowing through the channel screen 10, such that the liquid phase of the heat exchanger fluid carried in the first fluid flow 5 is distributed in the gas phase of the heat exchanger fluid, and is uniformly distributed in the fluid flow 5 downstream of the channel screen 11 on the fluid pipes 6, 12.

[0039] about Figure 2 and Figure 3 It must be noted that planes 28, indicated only partially by dashed lines, are provided, exemplarily passing through the center 17 of the sieve. Furthermore, planes 28 are parallel and aligned with the longitudinal central axis 2 of the tube, and are consistent with... Figure 2 The central axis 7 of the flat tubes, indicated by double-dotted lines and defined by flat tubes 6 and 12, is orthogonally aligned. In this way, plane 28 divides the channel screen 11 into a first side 29 facing away from the flat tubes and a second side 30 facing the flat tubes (see details). Figure 3 To achieve optimal distribution of the first fluid flow 5 on the flat tubes 6 and 12, channel screen holes 10 are provided on the first side 29 of the channel screen 11 facing away from the flat tubes. Here, it is feasible when the channel area of ​​the channel screen holes 10 reaches a minimum of 5% to a maximum of 50% of the surface area 31 of the channel screen holes 11.

[0040] According to a further exemplary embodiment, Figure 5 and Figure 6 Front views of the channel sieve 11 with channel sieve holes 10 are shown for heat exchanger 1. Figure 5 Channel screen 11 and Figures 1 to 4 The difference in the channel screen 11 is that only a single insertion lug 18 is now provided. According to Figure 6 The channel sieve 11 shown is Figure 5 The difference in the channel screen 11 shown is that the channel area of ​​the channel screen hole 10 is slightly larger.

Claims

1. A heat exchanger for thermal coupling of two fluids (1). - An inlet pipe (3) having a defined longitudinal central axis (2) is provided on the inlet pipe, with a fluid inlet (4) for supplying a first fluid flow (5) of heat exchanger fluid and a plurality of flat tubes (6, 12) adjacent to the fluid inlet (4) in the direction of the longitudinal central axis (2), the plurality of flat tubes (6, 12) being spaced apart from each other along the longitudinal central axis (2) and each communicating with the inlet pipe (3), such that the first fluid flow (5) can flow along a first fluid path (8) extending from the fluid inlet (4) through the inlet pipe (3) and the flat tubes (6, 12). - in, The flat tubes (6, 12) extend through a second fluid path (9) for a second fluid flow (32), such that the flat tubes (6, 12) can be flowed through by the first fluid flow (5) and surrounded by the second fluid flow (32). - Wherein, the heat exchanger (1) includes a channel sieve (10) through which a first fluid flow (5) can flow and interact with the heat exchanger fluid, the channel sieve (10) being fluidly connected in series with the flat tubes (6, 12). The channel screen (10) is disposed on the channel screen (11), which is located in the first fluid path (8) between the fluid inlet (4) and the flat tubes (6, 12). The gap (13) between the channel screen hole (10) of the channel screen (11) and the first flat tube (12) that is adjacent to and directly adjacent to the fluid inlet (4) in the direction of the longitudinal central axis (2) of the tube is adjusted to be 2.0 mm to 9.0 mm.

2. The heat exchanger (1) according to claim 1, characterized in that, The channel sieve (10) is positioned upstream of the flat tube (6, 12) relative to the first fluid flow (5).

3. The heat exchanger (1) according to claim 1 or 2, characterized in that, The channel sieve (10) is connected downstream of the fluid inlet (4) relative to the first fluid flow (5).

4. The heat exchanger (1) according to claim 1, characterized in that, The gap is 3.0 mm to 6.0 mm.

5. The heat exchanger (1) according to claim 1 or 2, characterized in that, The channel screen (10) is disposed on a channel screen (11) including a surrounding outer edge (14), the channel screen (11) supporting itself at least partially in contact with and optionally in a fluid-tight manner on at least one inner circumferential surface (15, 33) of the inflow pipe (3) via the surrounding outer edge.

6. The heat exchanger (1) according to claim 5, characterized in that, The outer edge (14) includes or forms a reinforcing member (16) that reinforces the channel screen (11) to resist shape changes, wherein the outer edge (14) is implemented to have a thickness of 1.4 mm to 3.0 mm.

7. The heat exchanger (1) according to claim 1 or 2, characterized in that, The channel screen (10) is disposed on the channel screen (11), the channel screen including at least one insert lug (18) that protrudes radially outward relative to the screen center (17) of the channel screen (11), the at least one insert lug being inserted into a lug groove (19) disposed on the inflow pipe (3) and complementary to the at least one insert lug (18) to fix the channel screen (11) to the inflow pipe (3) in a form-fitting and / or non-form-fitting manner.

8. The heat exchanger (1) according to claim 5, characterized in that, The inflow pipe (3) is implemented to have two parts, for this purpose, the inflow pipe is divided into a longitudinal lower shell (22) and a longitudinal upper shell (23) along the longitudinal central axis (2) of the pipe, wherein the outer edge (14) of the channel screen (11) is divided into a first circumferential receiving portion (24) for receiving the longitudinal lower shell (22) and a second circumferential receiving portion (25) for receiving the longitudinal upper shell (23) which is recessed relative to the first circumferential receiving portion (24).

9. The heat exchanger (1) according to claim 1 or 2, characterized in that, - The channel screen openings (10) are disposed on the channel screen (11), the channel screen including or forming at least one flow separation edge (26) that at least partially frames the channel screen openings (10), and / or, - Wherein, it is feasible that the at least one flow separation edge (26) fluidly interacts with the fluid flow (5) flowing through the channel sieve (10) such that the liquid phase of the heat exchanger fluid carried in the first fluid flow (5) is distributed in the gas phase of the heat exchanger fluid and is uniformly distributed in the fluid flow (5) downstream of the channel sieve (11) on the flat tube (6, 12).

10. The heat exchanger (1) according to claim 1 or 2, characterized in that, The channel sieve (10) defines a circular segmental opening profile (27).

11. The heat exchanger (1) according to claim 1 or 2, characterized in that, The channel screen holes (10) are disposed on the channel screen (11) defining the screen center (17), wherein a plane (28) extending parallel to the longitudinal central axis (2) of the tube extends through the screen center (17) and is orthogonally aligned with the central axis (7) of the flat tube defined by the flat tubes (6, 12), such that the plane (28) divides the channel screen (11) into a first side (29) away from the flat tube and a second side (30) facing the flat tube, wherein the channel screen holes (10) are disposed on the first side (29) of the channel screen (11) away from the flat tube.

12. The heat exchanger (1) according to claim 1 or 2, characterized in that, - The channel sieve holes (10) are disposed on the channel sieve (11), the channel sieve defining a surface area (31), wherein the channel area of ​​the channel sieve holes (10) is at least 5% of the surface area (31).

13. The heat exchanger (1) according to claim 1 or 2, characterized in that, - The channel sieve holes (10) are disposed on the channel sieve (11), the channel sieve defining a surface area (31), wherein the channel area of ​​the channel sieve holes (10) is 25% to 50% of the surface area (31).

14. The heat exchanger (1) according to claim 1 or 2, characterized in that, - The channel sieve holes (10) are disposed on the channel sieve (11), the channel sieve defining a surface area (31), wherein the channel area of ​​the channel sieve holes (10) is 25% to 75% of the surface area (31).

15. The heat exchanger (1) according to claim 1 or 2, characterized in that, - The channel sieve holes (10) are disposed on the channel sieve (11), the channel sieve defining a surface area (31), wherein the channel area of ​​the channel sieve holes (10) is 25%, 50%, or 75% of the surface area (31).

16. The heat exchanger (1) according to claim 1 or 2, characterized in that, - The channel sieve holes (10) are disposed on the channel sieve (11), the channel sieve defining a surface area (31), wherein the channel area of ​​the channel sieve holes (10) is at most 75% of the surface area (31).

17. The heat exchanger (1) according to claim 1 or 2, characterized in that, - The channel sieve holes (10) are disposed on the channel sieve (11), the channel sieve defining a surface area (31), wherein the channel area of ​​the channel sieve holes (10) is greater than 75% of the surface area (31).

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