Pulsating Heat Pipe Heatsink

Abstract

The invention relates to a pulsating heat pipe heat sink (10; 10a; 10b) with a housing (12; 12a; 12b) in which two fluidically separated channels (26; 26a; 26b, 28; 28a; 28b) for a cooling medium are arranged, wherein the two meandering channels (26; 26a; 26b, 28; 28a; 28b) each have first channel sections (30, 32) arranged parallel to each other and arcuate second channel sections (34, 36) or return sections (38; 38a, 40) connecting the first channel sections (30, 32), with an evaporator section (16) for arranging at least one heat-generating component and a condenser section (22) arranged at a distance from the evaporator section (16), wherein at least in the evaporator section (16) the first channel sections (30, 32) of the two channels (26; 26a; 26b, 28; 28a; 28b) are arranged alternately next to each other in a first plane (A) in a direction perpendicular to the longitudinal direction of the first channel sections (30, 32).

Description

Technical field

[0001] The invention relates to a pulsating heat pipe heat sink which is characterized by particularly safe operation when a channel filled with cooling medium has a leak. State of the art

[0002] From DE 10 2021 204 769 A1 of the applicant, a pulsating heat pipe cooling element with the features of the preamble of claim 1 is known. The known heat pipe cooling element, hereinafter referred to simply as a cooling element, has the special feature that it has two fluidically separated channels, each of which is meandering in shape, with the channels being arranged alternately next to each other. Furthermore, due to their construction consisting of sheet metal parts, the channels have a height offset from each other. The aforementioned document also discloses an embodiment in which channels are formed in several stacks of sheet metal arranged one above the other and connected to each other, but the respective channels are fluidically connected to each other via openings formed between the stacks of sheet metal. Disclosure of the invention

[0003] The pulsating heat pipe heat sink according to the invention, with the features of claim 1, has the advantage that, despite its simple and compact design, it enables reliable cooling of a heat-generating component located in an evaporator section in the event of a leak in one channel. This is particularly relevant in the context of electromobility or autonomous driving, as increased safety requirements are placed on the operation of the heat sink in the event of such a failure. The invention is based on the idea of ​​ensuring, through an intertwined geometry of the two channels, that the heat-generating component located in the evaporator section is nevertheless adequately cooled by the remaining channel in the event of a failure or leak in one channel.

[0004] In light of the above explanations, a pulsating heat pipe heat sink with the features of claim 1 therefore comprises a housing in which two fluidically separated channels, each for a different cooling medium, are arranged. The cooling medium in the two channels can be the same or different. The two meandering channels each have first channel sections arranged parallel to each other and arc-shaped second channel sections or return sections connecting the first channel sections. Furthermore, an evaporator section for arranging at least one heat-generating component is provided, as well as a condenser section arranged at a distance from the evaporator section.At least in the evaporator section, the first channel sections of the two channels are arranged alternately side by side in a first plane in a direction perpendicular to the longitudinal direction of the first channel sections. According to the invention, the two channels, at least in the evaporator section, form two separate planes of first channel sections arranged side by side, wherein in a second plane, extending above and below the first plane, the first channel sections of the two channels are also arranged alternately side by side in a direction perpendicular to the longitudinal direction of the first channel sections. Furthermore, the first channel sections of the two channels in the two planes are arranged with an offset to each other perpendicular to the longitudinal direction of the first channel sections.

[0005] Advantageous further developments of the Pulsating Heat Pipe cooling body according to the invention are listed in the dependent claims.

[0006] To create the interlinking or switching between the individual levels of the two channels, it is provided that the second channel sections or the return sections open onto opposite sides in different levels and are each connected to a first channel section.

[0007] With regard to the switching of channels between the two levels, it is preferably provided that the second channel sections or the return sections open into the two different levels on opposite sides and are each connected to a first channel section of the respective first or second channel.

[0008] Regarding the fluid flow in the second channel sections and the return sections, there are two geometrically preferred designs in particular: In a first variant, it is provided that the second channel sections or the return sections are designed as a connecting section running diagonally between the planes.

[0009] As an alternative to the first-mentioned variant, it is also conceivable that the second channel sections or the return sections between the two opposite sides are designed as a step-shaped connecting section.

[0010] In order to achieve equally good cooling effects in different directions, it may also be provided that the two channels, possibly with the exception of supply channels, are designed to be mirror-symmetrical to a straight line running parallel to the first channel sections.

[0011] The simplest manufacturing solution for changing the levels of the individual channels in the second channel sections or the return sections is to design the housing, including the channels arranged within it, as a single unit manufactured using an additive process. Alternatively, the housing can also be formed by combining components produced through primary and / or secondary forming processes.

[0012] To fill the two channels with the respective cooling medium, it is provided that each can be filled with the cooling medium via a lockable supply channel.

[0013] The invention further comprises a pulsating heat pipe heat sink, which is designed in particular in the manner described above according to the invention. The heat sink comprises two fluidically separated channels, in particular meander-shaped channels, which can be filled with one (and the same) cooling medium via a common supply channel, wherein the two channels are connected to each other by a connecting channel, and wherein the connecting channel is designed to be closed after filling with the cooling medium in order to form the fluidically separated two channels.

[0014] With regard to this general inventive concept of using a single supply channel for the (initial) filling of the two channels with the cooling medium, there are different embodiments: In a first embodiment, it is conceivable that the connecting channel is formed in a region of the two channels spaced apart from the supply channel. Alternatively, it is also conceivable that the supply channel opens into the connecting channel.

[0015] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments of the invention and from the drawings. Brief description of the drawings Fig. Figure 1 shows a sectional view of a pulsating heat pipe heat sink according to the invention with fluidically separated channels arranged on two levels, Fig. 2 and Fig. 3 partial cross-sections each in plane II-II of the Fig. 1. when the two channels are arranged differently in the different planes, Fig. 4 to Fig. 6 partial cross-sections each in plane IV-IV of the Fig. 1 in the case of different geometric designs of a connecting section between the two levels of the channels, Fig. 7 a sectional view of a heat sink with two fluidically separated channels that can be filled with cooling medium via a common supply channel and Fig. 8 a sectional view according to the Fig. 7 in a modified arrangement of a supply channel. Embodiments of the invention

[0016] Identical elements or elements with the same function are provided with the same reference numbers in the figures.

[0017] In the Fig. Figure 1 shows a heat pipe heat sink 10, hereinafter referred to simply as heat sink 10, which serves to cool at least one heat-generating component (not shown) during operation. The component may, in particular, be an electrical or electronic power component such as a power IC or a similar component.

[0018] The heat sink 10 has a metal housing 12, which is either multi-part or monolithic and, in the illustrated embodiment, is cuboid in shape with a rectangular base. Through-openings 14 are provided in the corner regions of the housing 12 for mounting the heat sink 10 to an assembly (not shown).

[0019] The heat sink 10 has an evaporator area 16, which in the exemplary embodiment is square and surrounded by a boundary 15, in the area of ​​which on the top or bottom of the housing 12, i.e. in a plane parallel to the drawing plane of the Fig. In the plane 1, the aforementioned component to be cooled is thermally connected to the heat sink 10. The connection between the component and the housing 12 can be made in a manner known per se by means of a thermally conductive adhesive or by a mechanical connection to the heat sink 10.

[0020] The evaporator section 16 is surrounded by a rectangular intermediate section 20, defined by a boundary 18. The intermediate section 20 is in turn surrounded by a rectangular or frame-shaped condenser section 22, the outer side of which is defined by a boundary 24.

[0021] Within the housing 12, which is preferably at least partially manufactured using an additive manufacturing process, two fluidically separated channels 26, 28 are formed. The two channels 26, 28 extend essentially between the evaporator section 16 and the condenser section 22, or even project slightly beyond it laterally. The two channels 26, 28 each have first channel sections 30, 32 arranged parallel to each other, with two immediately adjacent first channel sections 30, 32 being connected to each other by an arc-shaped second channel section 34, 36. The two first channel sections 30, 32 of the two channels 26, 28, which are spaced as far apart as possible, are further connected to each other via a return section 38, 40 running perpendicular to the longitudinal direction of the first channel sections 30, 32.

[0022] The two return sections 38, 40 are each connected to a separate supply channel 42, 44, which serves to fill the respective channel 26, 28 with an evaporable cooling medium. The supply channels 42, 44 open onto the outside of the housing 12 and are designed to be closable in a manner not shown. Furthermore, it can be seen from the Fig. 1. It can be seen that the arrangement of the channels 26, 28 and the evaporator area 16 is at least essentially mirror-symmetrical to a straight line 46.

[0023] Within channels 26 and 28, the evaporable cooling medium is arranged, which serves to cool the at least one heat-generating component in the evaporator section 16. When the cooling medium heats up, it evaporates, forming vapor bubbles. The cooling medium then flows via the intermediate section 20 into the condenser section 22, where it cools down or condenses before flowing back into the evaporator section 16. The operating principle of such a cooling element 10 is known per se and is therefore not described in detail.

[0024] The essential aspect of the invention is the arrangement and design of the first channel sections 30, 32 and the second channel sections 34, 36, as well as the return sections 38, 40. In particular, the illustration of the Fig. 1 to 3 show that the heat sink 10 is in a position perpendicular to the plane of the drawing. Fig. 1 or by the directional arrows 48 into the Fig. 2 and Fig. Figure 3 shows two planes A and B of first channel sections 30, 32 arranged one above the other. In each of the two planes A, B, the first channel sections 30, 32 of the two channels 26, 28 are arranged alternately next to each other, with a lateral offset x, y formed between the first channel sections 30, 32 in the different planes A, B in a direction perpendicular to the longitudinal direction of the first channel sections 30, 32. According to the illustration of the Fig. 2. Furthermore, it may be possible that the first channel sections 30, 32, which exemplarily have a square cross-section with rounded corners, are each aligned exactly in the respective plane A, B without any height offset to each other, or according to the representation of the Fig. 3 in the direction of the direction arrow 48 have a slight height offset h to each other.

[0025] Furthermore, it is essential that the two channels 26, 28 are interconnected. This interconnection is achieved through the specific design of the second channel sections 34, 36 and the return sections 38, 40. In particular, the transition between the individual interconnected first channel sections 30, 32 of channels 26, 28 on levels A, B takes place in the area of ​​the two second channel sections 34, 36 and the return sections 38, 40. The following section provides further details. Fig. 4 to 6 referred.

[0026] Based on the Fig. 4 It can be seen that the two first channel sections 30, 32 of the channel 26, 28, which run directly next to each other on different levels A, B, are connected to each other by means of a straight or diagonal (arc-shaped) connecting section 50 of the second channel section 34, 36.

[0027] In the Fig. Figure 5 shows that the opposite sides of the second channel section 34, 36 are connected to each other by a stepped connecting section 50a with an angular contour, instead of by means of a diagonally running connecting section 50. Fig. Figure 6 alternatively shows a connecting section 50b, which has rounded corners 52. The transition between levels A and B between two immediately adjacent first channel sections 30 and 32 of the two channels 26 and 28 thus takes place via the connecting sections 50, 50a, and 50b of the second channel sections 34 and 36.

[0028] In order to connect the two outermost first channel sections 30, 32 of the two channels 26, 28 to each other on different planes A, B by means of the return sections 38, 40, the corresponding return sections 38, 40 run perpendicular to the drawing plane of the Fig. 1 at an oblique angle.

[0029] In the Fig. 7 and Fig. Figure 8 shows cooling elements 10a, 10b, which also have two fluidically separated channels 26a, 28a and 26b, 28b, respectively. In the illustrated embodiment, the channels 26a, 28a and 26b, 28b interlock in a comb-like manner in a common plane; however, they can also run in different planes or be intertwined according to the geometry of the cooling element 10.

[0030] It is essential that both heat sinks 10a, 10b in their housing 12a, 12b each have only a single supply channel 54, 56, which serves for the (simultaneous) filling of the two channels 26a, 28a and 26b, 28b, respectively. The supply channel 54 of the heat sink 10a opens into the first channel 26a, specifically in the area of ​​a return section 38a. Furthermore, a connecting section 58 is provided between the two channels 26a, 28a, which is spatially separated from the supply channel 54.

[0031] In contrast, in the case of the heat sink 10b, the supply channel 56 leads directly into a connecting section 60, which connects the two channels 26b, 28b.

[0032] Both embodiments have in common that after the filling of the two channels 26a, 28a and 26b, 28b respectively, the respective connecting section 58, 60 is closed in a symbolically elliptical area 62 in a manner not shown, e.g. by a mechanical or other process step, in order to achieve two fluidically separated channels 26a, 28a and 26b, 28b respectively.

[0033] The cooling element 10, 10a, 10b described so far can be modified or adapted in a variety of ways without deviating from the inventive concept. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2021 204 769 A1

[0002]

Claims

[1] Pulsating heat pipe heat sink (10; 10a; 10b), comprising a housing (12; 12a; 12b) in which two fluidically separated channels (26; 26a; 26b, 28; 28a; 28b) for a cooling medium are arranged, wherein the two meandering channels (26; 26a; 26b, 28; 28a; 28b) each have first channel sections (30, 32) arranged parallel to each other and arcuate second channel sections (34, 36) or return sections (38; 38a, 40) connecting the first channel sections (30, 32), comprising an evaporator section (16) for arranging at least one heat-generating component and a condenser section 22) arranged at a distance from the evaporator section (16), wherein at least in the evaporator section (16) the first channel sections (30, 32) of the two channels (26; 26a; 26b, 28; 28a; 28b) are arranged alternately next to each other in a first plane (A) in a direction perpendicular to the longitudinal direction of the first channel sections (30, 32), characterized by, that the two channels (26; 26a; 26b, 28; 28a; 28b) form, at least in the evaporator region (16), two separate levels (A, B) with first channel sections (30, 32) arranged side by side, wherein in a second level (B) running above and below the first level (A), the first channel sections (30, 32) of the two channels (26; 26a; 26b, 28; 28a; 28b) are also arranged alternately side by side in a direction perpendicular to the longitudinal direction of the first channel sections (30, 32), and that the first channel sections (30, 32) of the two channels (26; 26a; 26b, 28; 28a; 28b) in the two levels (A, B) are connected by a direction perpendicular to the longitudinal direction of the first channel sections (30, 32) are arranged with an offset (x, y) to each other. [2] Heat sink according to claim 1, characterized by, that the second channel sections (34, 36) or the return sections (38; 38a, 40) open on opposite sides into the two different levels (A, B) and are connected there to a first channel section (30, 32) of the respective first or second channel (26; 26a; 26b, 28; 28a; 28b). [3] Heat sink according to claim 2, characterized by , that the second channel sections (30, 32) or the return sections (38; 38a, 40) are designed as a connecting section (50) running diagonally between the two planes (A, B). [4] Heat sink according to claim 2, characterized by , that the second channel sections (30, 32) or the return sections (38; 38a, 40) are designed as a step-like connecting section (50a; 50b) running between the two levels (A, B). [5] Heat sink according to any one of claims 1 to 4, characterized by, that the two channels (26; 26a; 26b, 28; 28a; 28b), possibly with the exception of supply channels (42, 44; 54; 56), are formed in a mirror-symmetrical manner to a straight line (46) running parallel to the first channel sections (30, 32). [6] Heat sink according to any one of claims 1 to 5, characterized by , that the housing (12; 12a; 12b) with the channels (26; 26a; 26b, 28; 28a; 28b) arranged therein is designed as a housing (12; 12a; 12b) produced in an additive process. [7] Heat sink according to any one of claims 1 to 6, characterized by , that the two channels (26, 28) can each be filled with the cooling medium via a lockable supply channel (42, 44). [8] Pulsating Heat Pipe cooling element (10a; 10b), in particular designed according to one of claims 1 to 6, with two fluidically separated, in particular meandering channels (26a; 26b, 28a; 28b) which can be filled with a cooling medium via a common supply channel (54; 56), wherein the two channels (26a; 26b, 28a; 28b) are connected to each other by a connecting section (58; 60), and wherein the connecting section (58; 60) is designed to be closed after filling with the cooling medium in order to form the fluidically separation of the two channels (26a; 26b, 28a; 28b). [9] Heat sink according to claim 8, characterized by , that the connecting section (58) is formed in an area of ​​the two channels (26a, 28a) spaced apart from the supply channel (54). [10] Heat sink according to claim 8, characterized by , that the supply channel (56) empties into the connecting channel (60).

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