Pulsating heat pipe heat sink

Abstract

The invention relates to a pulsating heat pipe heat sink (10; 10a; 10b), comprising: a housing (12; 12a; 12b) containing two fluidically separated channels (26; 26a; 26b, 28; 28a; 28b), each for conveying a cooling medium, wherein the two meandering channels (26; 26a; 26b, 28; 28a; 28b) each have first channel portions (30, 32) arranged parallel to one another, and arcuate second channel portions (34, 36) or return portions (38; 38a, 40) which connect the first channel portions (30, 32); an evaporator region (16) in which at least one heat-generating component can be disposed; and a condenser region (22) spaced at a distance from the evaporator region (16), wherein, at least in the evaporator region (16), the first channel portions (30, 32) of the two channels (26; 26a; 26b, 28; 28a; 28b) are arranged alternately next to one another in a first plane (A) in a direction perpendicular to the longitudinal direction of the first channel portions (30, 32).

Description

[0001] R.411593

[0002] Description

[0003] title

[0004] Pulsating Heat Pipe Heatsink

[0005] Technical field

[0006] 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.

[0007] State of the art

[0008] From DE 102021 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, the channels have a height offset from each other due to their construction consisting of sheet metal parts. 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.

[0009] Disclosure of the invention

[0010] The pulsating heat pipe heat sink according to the invention, with the features of claim 1, has the advantage that, with a simple and compact design, it provides reliable cooling of a heat-generating element arranged in an evaporator area in the event of a leak in a channel.

[0011] - 2 -

[0012] This enables the component to function as intended. This is particularly relevant in the context of electromobility or the autonomous operation of a vehicle, 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 interwoven geometry of the two channels, that in the event of a failure or leakage of one channel, the heat-generating component located in the evaporator area is nevertheless adequately cooled by the remaining channel.

[0013] 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 area, the first channel sections of the two channels are arranged alternately next to each other in a first plane in a direction perpendicular to the longitudinal direction of the first channel sections.

[0014] According to the invention, the two channels, at least in the evaporator area, form two separate planes of adjacent first channel sections, wherein in a second plane extending above and below the first plane, the first channel sections of the two channels are also arranged alternately adjacent to one another 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.

[0015] Advantageous embodiments of the pulsating heat pipe heat sink according to the invention are listed in the dependent claims. R.411593

[0016] - 3 -

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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 forming and / or forming processes. R.411593

[0023] - 4 - llm To fill the two channels with the respective cooling medium, it is provided that they can each be filled with the cooling medium via a lockable supply channel.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] Brief description of the drawings

[0028] Fig. 1 shows a sectional view of a pulsating heat pipe heat sink according to the invention with fluidically separated channels arranged on two levels,

[0029] Fig. 2 and R.411593

[0030] - 5 -

[0031] Fig. 3 shows partial cross-sections in the plane 11-11 of Fig. 1 with different arrangements of the two channels in the different planes.

[0032] Fig. 4 to

[0033] Fig. 6 shows partial cross-sections in plane IV-IV of Fig. 1 for different geometric configurations of a connecting section between the two planes of the channels.

[0034] Fig. 7 shows 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

[0035] Fig. 8 shows a sectional view corresponding to Fig. 7 in a modified arrangement of a supply channel.

[0036] Embodiments of the invention

[0037] Identical elements or elements with the same function are provided with the same reference numbers in the figures.

[0038] 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. This component can be, in particular, an electrical or electronic power component such as a power IC or a similar component.

[0039] 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). R.411593

[0040] - 6 -

[0041] The heat sink 10 has an evaporator area 16, which in the exemplary embodiment is square and surrounded by a boundary 15. Within this area, on the top or bottom of the housing 12 (i.e., in a plane parallel to the plane of Fig. 1), the at least one 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, either by a thermally conductive adhesive or by a mechanical connection to the heat sink 10.

[0042] 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.

[0043] 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.

[0044] 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 on the outside of the housing 12 and are designed to be closable in a manner not shown. Furthermore, as can be seen from Fig. 1 R.411593

[0045] - 7 - it is evident that the arrangement of the channels 26, 28 or the evaporator area 16 is at least essentially mirror-symmetrical to a straight line 46.

[0046] 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.

[0047] Essential to 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, it can be seen from the illustrations in Figures 1 to 3 that the heat sink 10 has two planes A and B of first channel sections 30, 32 arranged one above the other in a direction perpendicular to the plane of Figure 1 or indicated by the direction arrows 48 in Figures 2 and 3. 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. As shown in Figures 1 to 3,2. 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, as shown in Fig. 3, have a slight height offset h to each other in the direction of the arrow 48.

[0048] 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 R.411593 on levels A, B occurs in the area of ​​the two second channel sections 34, 36 and the return sections 38, 40.

[0049] - 8 - first channel sections 30, 32 of channels 26, 28. Reference is made below to the illustrations in Figs. 4 to 6.

[0050] Fig. 4 shows that the two first channel sections 30, 32 of the channel 26, 28, which run directly next to each other on different planes 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.

[0051] Figure 5 shows that the opposite sides of the second channel section 34, 36 are connected to each other not by means of a diagonally extending connecting section 50, but by a stepped connecting section 50a with an angular contour. Figure 6 alternatively shows a connecting section 50b, which has rounded corners 52. The transition between levels A, B between two immediately adjacent first channel sections 30, 32 of the two channels 26, 28 thus takes place via the connecting sections 50, 50a, 50b of the second channel sections 34, 36.

[0052] 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 plane of Fig. 1 at an oblique angle.

[0053] Figures 7 and 8 show 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.

[0054] 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 to (simultaneously) fill the two channels 26a, 28a and 26b, 28b, respectively. The supply channel 54 of heat sink 10a opens into the first channel 26a, R.411593

[0055] - 9 - namely 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.

[0056] 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.

[0057] Both embodiments have in common that, after filling 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.

[0058] 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.

Claims

R.411593 - 10 - 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) in a direction perpendicular to the longitudinal direction of the first channel sections (30, 32) in a first plane (A), characterized in that the two channels (26; 26a; 26b, 28; 28a; 28b) form at least in the evaporator area (16) two separate planes (A, B) with first channel sections (30, 32) arranged side by side, wherein in a second plane (B) extending above or below the first plane (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) are arranged in the two planes (A, B) with an offset (x, y) to each other perpendicular to the longitudinal direction of the first channel sections (30, 32).; R.411593 - 11 - 2. Cooling sink according to claim 1, characterized in that the second channel sections (34, 36) or the return sections (38; 38a, 40) open on opposite sides in the two different planes (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. Cooling sink according to claim 2, characterized in 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. Cooling sink according to claim 2, characterized in 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 planes (A, B).

5. Heat sink according to one of claims 1 to 4, characterized in that the two channels (26; 26a; 26b, 28; 28a; 28b), optionally excluding supply channels (42, 44; 54; 56), are formed in a mirror-symmetrical manner with respect to a straight line (46) running parallel to the first channel sections (30, 32).

6. Heat sink according to one of claims 1 to 5, characterized in 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 manufacturing process.

7. Heat sink according to one of claims 1 to 6, characterized in that, R.411593 - 12 - 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 in that the connecting section (58) is formed in a region of the two channels (26a, 28a) spaced apart from the supply channel (54).

10. Cooling element according to claim 8, characterized in that the supply channel (56) opens into the connecting channel (60).

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