JP2009275945A - Ebullient cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ebullient cooling device can improve heat exchanging efficiency at a condensing section for condensing a refrigerant. <P>SOLUTION: A radiation core section 4 includes a tube 41 forming a refrigerant pathway in which the refrigerant is circulated, the condensing section 413 having inner fins 410 for increasing a heat transferring area with the refrigerant and condensing the refrigerant boiled in a refrigerant tank 3 is formed inside of the tube 41, the inside of the condensing section 413 is divided into a plurality of condensing pathways 413a by the inner fins 410, a steam pathway 411 disposed at a downstream side of the cooling air flow of the condensing section 413 for allowing the refrigerant boiled in the refrigerant tank 3 to flow therein, and a distributing pathway 412 for distributing the refrigerant from the steam pathway 411 to the plurality of condensing pathways 413a are formed on a region excluding the condensing section 413 inside of the tube 41, and the steam pathway 411 and the distributing pathway 412 are respectively formed so that a crosssectional area of the pathway is gradually reduced from the upstream side toward the downstream side of the refrigerant flow. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a boiling cooling device that absorbs heat from a heating element by boiling a refrigerant with heat generated in the heating element.

An example of the boiling cooling device is disclosed in Patent Document 1. The boiling cooling device disclosed in Patent Document 1 includes a refrigerant tank having a heat generating element attached to a side surface, and a heat dissipating unit provided in an upper part of the refrigerant tank. Further, an inner fin for increasing the heat transfer area with the refrigerant is inserted inside the tube constituting the heat radiating unit, and a condensing unit for condensing the refrigerant vapor boiling in the refrigerant tank is formed. The refrigerant passage in the condensing part is divided into a plurality of small passages by joining the corrugated tops of the inner fins. In addition, a vapor passage through which the refrigerant boiled in the refrigerant tank flows and a distribution passage that distributes the refrigerant vapor from the vapor passage to a plurality of small passages in the condensation portion are formed in a portion excluding the condensation portion in the tube. Yes.
JP 2000-260919 A

  However, in the boiling cooling device described in Patent Document 1, the refrigerant vapor that passes through the distribution passage is easily distributed to the small passages arranged on the downstream side in the refrigerant flow direction in the distribution passage among the plurality of small passages, Of the plurality of small passages, it is difficult to distribute to the small passages arranged on the upstream side in the refrigerant flow direction in the distribution passage. That is, since the refrigerant vapor is not evenly distributed to all the small passages, there is a problem that the heat exchange efficiency (condensation efficiency) in the condensing part is lowered.

  Further, in the boiling cooling device described in Patent Document 1, since the cross-sectional area of the steam passage is constant throughout the refrigerant flow direction, the liquid-phase refrigerant ejected from the refrigerant tank directly flows into the condensing unit, Thereby, there exists a possibility that the heat exchange efficiency in a condensation part may fall further.

  An object of this invention is to provide the boiling cooling device which can improve the heat exchange efficiency in the condensation part which condenses a refrigerant | coolant in view of the said point.

  In order to achieve the above object, in the invention according to claim 1, the heat radiating core portion (4) has a tube (41) that forms a refrigerant passage through which the refrigerant flows, and the tube (41) has an inside. Is provided with a condensing area increasing member (410) for increasing the heat transfer area with the refrigerant, forming a condensing part (413) for condensing the refrigerant boiled in the refrigerant tank (3), and condensing part (413). The inside is divided into a plurality of condensing passages (413a) by a condensing area increasing member (410), and a portion of the inside of the tube (41) excluding the condensing part (413) is of the condensing part (413). A vapor passage (411) that is arranged on the downstream side of the external fluid flow and into which the refrigerant boiled in the refrigerant tank (3) flows, and a distribution passage that distributes the refrigerant from the vapor passage (411) to the plurality of condensation passages (413a) ( 412) and formed Are, steam passage (411) and distribution passage (412), respectively, gradually cross-sectional area toward the downstream side from the refrigerant flow upstream side is characterized in that it is formed to be smaller.

  In this manner, the distribution passage (412) is formed in such a manner that the passage cross-sectional area gradually decreases from the refrigerant flow upstream side to the downstream side, whereby the refrigerant tank (3) boils in the distribution passage (412). The refrigerant (hereinafter referred to as refrigerant vapor) can be easily distributed to the condensing passage (413a) that is disposed on the upstream side in the refrigerant flow direction in the distribution passage (412) among the plurality of condensing passages (413a). . Therefore, the refrigerant vapor can be uniformly distributed to the plurality of condensing passages (413a), so that the heat exchange efficiency in the condensing unit (413) can be improved.

  Further, by forming the steam passage (411) so that the passage cross-sectional area gradually decreases from the upstream side to the downstream side of the refrigerant flow, the liquid phase refrigerant is transferred from the refrigerant tank (3) to the vapor passage (411). Even when the refrigerant flows in, the passage cross-sectional area at the downstream end of the refrigerant flow in the vapor passage (411) is small, so that the liquid refrigerant can be prevented from flowing into the condensing part (413). Accordingly, it is possible to further improve the heat exchange efficiency in the condensing unit (413).

  Furthermore, by disposing the steam passage (411) on the downstream side of the external fluid flow with respect to the condensing part (413), in the steam passage (411), the heated external fluid and the refrigerant after passing through the condensing part (413). Since heat exchange is performed with the steam, the refrigerant steam can be prevented from condensing in the steam passage (411). Thereby, the refrigerant vapor easily passes through the vapor passage (411), so that the heat exchange efficiency in the condensing unit (413) can be further improved.

  In the invention according to claim 2, the condensation area increasing member (410) has a refrigerant flow direction in the condensation passage (413a) in which the refrigerant tank (3) and the heat dissipating core part (4) are arranged (X1). ) And an inclination with respect to the flow direction (X2) of the external fluid.

  According to this, the tube (41) is used as both a horizontal blowing type boiling cooling device in which the flow direction of the external fluid matches the horizontal direction and a vertical blowing type boiling cooling device in which the flow direction of the external fluid matches the direction of gravity. Can be applied. That is, it becomes possible to share the tube (41) between the horizontal blow type boiling cooling device and the vertical blow type boiling cooling device.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view showing a boiling cooling device 1 according to the first embodiment, and FIG. 2 is a cross-sectional view taken along line AA of FIG. In addition, the broken-line arrow in FIG. 2 has shown the flow of the refrigerant | coolant.

  As shown in FIG. 1 and FIG. 2, the boiling cooling device 1 of the present embodiment cools the heating element 2 (see FIG. 2) by repeating boiling and condensing of the refrigerant. The refrigerant tank 3 for storing the refrigerant) and the heat radiating core portion 4 assembled on the surface of the refrigerant tank 3 are manufactured by integral brazing. The heating element 2 is, for example, an IGBT module that constitutes an inverter circuit of an electric vehicle, and is fixed in close contact with the surface of the refrigerant tank 3 with bolts (not shown) or the like. The refrigerant tank 3 is a flat box-like container in which a plurality of plates 30 are joined in a stacked state and a space in which liquid refrigerant is stored is formed inside.

  In the present embodiment, the heat radiating core portion 4 is disposed on the upper surface (hereinafter referred to as the upper surface 3a) of the refrigerant tank 3, and the lower surface 3b (FIG. 2) that is the surface opposite to the upper surface 3a in the refrigerant tank 3. The heating element 2 is arranged. Moreover, the refrigerant tank 3 is arrange | positioned so that the upper surface 3a may become parallel to a horizontal surface. For this reason, the arrangement | positioning direction (henceforth the arrangement | positioning direction X1) of the refrigerant | coolant tank 3 and the thermal radiation core part 4 corresponds with the gravity direction.

  The heat radiating core portion 4 has a plurality of tubes 41 assembled substantially upright on the one surface 3 a of the refrigerant tank 3, and waved heat radiating fins 42 joined to the outer surface of each tube 41. The tube 41 forms a refrigerant passage through which the refrigerant flows. The heat radiating fins 42 increase the heat transfer area with the cooling air blown to the heat radiating core portion 4. In the present embodiment, the flow direction of the cooling air (hereinafter referred to as cooling air flow direction X2) coincides with the horizontal direction. The cooling air corresponds to the external fluid of the present invention.

  As shown in FIG. 2, an inner fin 410 is disposed inside the tube 41, and a condensing unit 413 that condenses the refrigerant boiled in the refrigerant tank 3 is formed. The inner fin 410 is a thin metal plate (for example, an aluminum plate) excellent in thermal conductivity, which is alternately bent at a predetermined pitch and formed into a corrugated shape. The top of the corrugated inner fin 410 is formed on the inner wall surface of the tube 41. The tube 41 is reinforced by joining, and the performance is improved by increasing the heat transfer area with the refrigerant. The inner fin 410 corresponds to the condensation area increasing member of the present invention.

  The refrigerant passage in the condensing unit 413 is divided into a plurality of condensing passages 413 a by joining the wave-shaped tops of the inner fins 410. And the inner fin 410 is arrange | positioned so that the extending direction of a waveform top part, ie, the flow direction of the refrigerant | coolant in the condensation channel | path 413a, may incline with respect to the arrangement | positioning direction X1 and the cooling air flow direction X2. Specifically, the inner fins 410 of the present embodiment are arranged to be inclined with respect to the arrangement direction X1 so that the flow direction of the refrigerant in the condensing passage 413a is on the upstream side of the cooling air flow as it goes downward. Has been.

  Further, the inner fins 410 are arranged to be biased upstream of the cooling air flow in the tube 41. Thereby, in the part except the condensing part 413 inside the tube 41, the steam path 411 secured on the downstream side of the cooling air flow of the inner fin 410, that is, the condensing part 413, and the upper side of the inner fin 410, that is, the refrigerant tank. 3 is formed on the side opposite to 3. The refrigerant that has boiled in the refrigerant tank 3 flows into the vapor passage 411. The distribution passage 412 communicates with the vapor passage 411 so as to distribute the refrigerant from the vapor passage 411 to the plurality of condensation passages 413a. The steam passage 411, the distribution passage 412 and the condensing passage 413a constitute the refrigerant passage.

  The vapor passage 411 is formed so that the passage cross-sectional area gradually decreases from the refrigerant flow upstream side toward the downstream side. In the present embodiment, the steam passage 411 has a passage sectional area that gradually decreases from the lower side toward the upper side. The distribution passage 412 is formed so that the passage sectional area gradually decreases from the refrigerant flow upstream side to the downstream side. In the present embodiment, the distribution passage 412 has a passage sectional area that gradually decreases from the cooling air flow downstream side toward the upstream side.

  In the tube 41, both side surfaces (outer surfaces) that are joint surfaces with the radiation fins 42 are arranged along the cooling air flow direction X2, and at this time, the condensation passage 412 is upstream of the cooling air flow from the steam passage 411. The direction of the tube 41 is specified so that it may be located in FIG. Further, a portion of the tube 41 where the vapor passage 411 and the distribution passage 412 are connected, that is, a corner portion corresponding to the end of the vapor passage 411 on the side far from the refrigerant tank 3 has an R shape.

  Above the portion of the refrigerant tank 3 where the heat generating element 2 is fixed, the refrigerant (refrigerant vapor) boiled by the heat of the heat generating element 2 is introduced into the tube 41 in communication with the vapor passage 411 of the tube 41. A refrigerant vapor inlet 31 is formed. Further, on the upstream side of the cooling air flow of the refrigerant vapor inlet 31 in the refrigerant tank 3, the liquid refrigerant outlet communicates with the condensation passage 413 a of the tube 41 and allows the refrigerant (liquid refrigerant) condensed in the tube 41 to flow into the refrigerant tank 3. 32 is formed.

  Returning to FIG. 1, the radiating fin 42 is provided only in a portion corresponding to the distribution passage 412 and the condensing unit 413 on the outer surface of the tube 41, and is not provided in a portion corresponding to the vapor passage 411. Moreover, the 1st fin press board part 43 which is joined to the radiation fin 42 and hold | suppresses the radiation fin 42 from an upper side is attached to the both ends of the lamination direction (henceforth the tube lamination direction X3) of the tube 41 in the radiation core part 4. Each is arranged. In addition, the heat dissipating core part 4 is joined to the heat dissipating fins 42 and the tubes 41 on the side far from the refrigerant tank 3 in the arrangement direction X1, that is, on the upper side in the gravity direction, and from the side far from the refrigerant tank 3 in the arrangement direction X1. A second fin pressing plate portion 44 that presses the heat radiating fins 42 is provided.

  As described above, the distribution passage 412 is formed so that the passage cross-sectional area gradually decreases from the refrigerant flow upstream side to the downstream side, so that the refrigerant vapor boiled in the refrigerant tank 3 in the distribution passage 412 can be obtained. Of the plurality of condensing passages 413a, the condensing passage 413a can be easily distributed to the condensing passage 413a arranged on the upstream side of the distribution passage 412 in the refrigerant flow direction. That is, in the present embodiment, it is possible to distribute more refrigerant vapor to the upstream condensing passage 413a in the refrigerant flow direction, in which refrigerant vapor is hardly distributed. Therefore, since the refrigerant vapor can be uniformly distributed to the plurality of condensing passages 413a, the heat exchange efficiency in the condensing unit 413 can be improved.

  Further, by forming the vapor passage 411 so that the passage cross-sectional area gradually decreases from the upstream side to the downstream side of the refrigerant flow, even when liquid refrigerant ejected from the refrigerant tank 3 flows into the vapor passage 411. In addition, since the passage cross-sectional area at the downstream end of the refrigerant flow in the vapor passage 411 is small, the liquid refrigerant can be prevented from flowing into the condensing unit 413. Therefore, the heat exchange efficiency in the condensing unit 413 can be further improved.

  Further, by disposing the steam passage 411 on the downstream side of the cooling air flow from the condensing unit 413, in the steam passage 411, heat exchange is performed between the cooling air that has been heated after passing through the condensing unit 413 and the refrigerant vapor. As a result, the refrigerant vapor can be prevented from condensing in the vapor passage 411. Thereby, since the refrigerant vapor easily passes through the vapor passage 411, the heat exchange efficiency in the condensing unit 413 can be further improved.

  In addition, the inner fin 410 is arranged so that the refrigerant flow direction in the condensing passage 413a is inclined with respect to the arrangement direction X1 and the cooling air flow direction X2, so that the tube 41 is as in the present embodiment. The present invention is applied to both a horizontal blow type boiling cooling device in which the cooling air flow direction X2 coincides with the horizontal direction and a vertical blow type boiling cooling device in which the cooling air flow direction X2 coincides with the direction of gravity as in the second embodiment described later. be able to. That is, the tube 41 can be shared by the horizontal blow type boiling cooling device and the vertical blow type boiling cooling device.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a perspective view showing the boiling cooling device 1 according to the second embodiment, and FIG. 4 is a partial cross-sectional view taken along line BB of FIG. In addition, the broken line arrow in FIG. 4 has shown the flow of the refrigerant | coolant.

  As shown in FIGS. 3 and 4, in this embodiment, the longitudinal direction of the refrigerant tank 3 coincides with the direction of gravity. And one heat radiating core part 4 is arrange | positioned at one outer wall surface 3a of the refrigerant | coolant tank 3 so that the arrangement | positioning direction X1 of the refrigerant | coolant tank 3 and the heat radiating core part 4 may correspond with a horizontal direction. Further, the cooling air flow direction X2 of the present embodiment coincides with the direction of gravity.

  Six heating elements 2 are arranged on the lower side of the heat radiating core portion 4 on the outer wall surface 3 a of the refrigerant tank 3. The six heating elements 2 are arranged side by side in the vertical direction. That is, the two heat generating elements 2 are disposed at the lower end portion of the outer wall surface 3a, the two heat generating elements 2 are disposed immediately below the upper end portion of the outer wall surface 3a, that is, the heat radiating core portion 4, and the upper end portion of the outer wall surface 3a. Two heating elements 2 are disposed between the lower end portion and the lower end portion.

  Hereinafter, the two heating elements 2 arranged at the lower end portion of the outer wall surface 3 a are referred to as a lower heating element 21, and the two heating elements 2 arranged at the upper end portion of the outer wall surface 3 a, that is, immediately below the heat radiating core portion 4. Is referred to as the upper heating element 22, and the two heating elements 2 disposed between the lower heating element 21 and the upper heating element 22 are referred to as the middle heating element 23. The two lower heating elements 21, the two upper heating elements 22, and the two middle heating elements 23 are arranged in the horizontal direction.

  As shown in FIG. 4, a condensing part 413 in which inner fins 410 are arranged is formed inside the tube 41. Further, the inner fin 410 is disposed such that the flow direction of the refrigerant in the condensing passage 413a is inclined with respect to the arrangement direction X1 and the cooling air flow direction X2 (that is, the direction of gravity). Specifically, the inner fin 410 of the present embodiment is arranged with respect to the arrangement direction X1 so that the flow direction of the refrigerant in the condensation passage 413a is closer to the refrigerant tank 3 toward the lower side, that is, the upstream side of the cooling air flow. It is arranged to be inclined.

  Further, the inner fins 410 are arranged to be biased upstream of the cooling air flow in the tube 41. As a result, the inner fin 410, that is, the steam passage 411 secured on the downstream side of the cooling air flow of the condensing unit 413 and the refrigerant tank 3 of the inner fin 410 are opposite to the inside of the tube 41 except the condensing unit 413. A distribution passage 412 secured on the side is formed.

  The vapor passage 411 is formed so that the passage cross-sectional area gradually decreases from the refrigerant flow upstream side toward the downstream side. In the present embodiment, the vapor passage 411 has a passage sectional area that gradually decreases from the side closer to the refrigerant tank 3 toward the side farther from the side. The distribution passage 412 is formed so that the passage sectional area gradually decreases from the refrigerant flow upstream side to the downstream side. In this embodiment, the distribution passage 412 has a passage cross-sectional area that gradually decreases from the cooling air flow downstream side to the upstream side, that is, from the upper side to the lower side.

  A refrigerant vapor inlet 31 is formed at the upper end of the refrigerant tank 3 so as to communicate with the vapor passage 411 of the tube 41 and allow the refrigerant (refrigerant vapor) boiled by receiving heat from the heating element 2 to flow into the tube 41. . Further, on the upstream side of the cooling air flow of the refrigerant vapor inlet 31 in the refrigerant tank 3, the liquid refrigerant outlet communicates with the condensation passage 413 a of the tube 41 and allows the refrigerant (liquid refrigerant) condensed in the tube 41 to flow into the refrigerant tank 3. 32 is formed.

  Returning to FIG. 3, first fin pressing plate portions 43 that are bonded to the heat radiation fins 42 and press the heat radiation fins 42 from the horizontal direction are disposed at both ends of the heat radiation core portion 4 in the tube stacking direction X <b> 3. In addition, the heat dissipating core part 4 is joined to the heat dissipating fin 42 and the tube 41 at the end of the disposing direction X1 far from the refrigerant tank 3, and holds the heat dissipating fin 42 from the distant side from the refrigerant tank 3 in the disposing direction X1. A two-fin holding plate portion 44 is provided.

  As described above, the distribution passage 412 is formed so that the passage cross-sectional area gradually decreases from the refrigerant flow upstream side to the downstream side, so that the refrigerant vapor boiled in the refrigerant tank 3 in the distribution passage 412 can be obtained. Of the plurality of condensing passages 413a, the condensing passage 413a can be easily distributed to the condensing passage 413a arranged on the upstream side of the distribution passage 412 in the refrigerant flow direction. Therefore, since the refrigerant vapor can be uniformly distributed to the plurality of condensing passages 413a, the heat exchange efficiency in the condensing unit 413 can be improved.

  Further, by forming the vapor passage 411 so that the passage cross-sectional area gradually decreases from the upstream side to the downstream side of the refrigerant flow, even when liquid refrigerant ejected from the refrigerant tank 3 flows into the vapor passage 411. In addition, since the passage cross-sectional area at the downstream end of the refrigerant flow in the vapor passage 411 is small, the liquid refrigerant can be prevented from flowing into the condensing unit 413. Therefore, the heat exchange efficiency in the condensing unit 413 can be further improved.

  Further, by disposing the steam passage 411 on the downstream side of the cooling air flow from the condensing unit 413, in the steam passage 411, heat exchange is performed between the cooling air that has been heated after passing through the condensing unit 413 and the refrigerant vapor. As a result, the refrigerant vapor can be prevented from condensing in the vapor passage 411. Thereby, since the refrigerant vapor easily passes through the vapor passage 411, the heat exchange efficiency in the condensing unit 413 can be further improved.

  In addition, the inner fin 410 is disposed such that the flow direction of the refrigerant in the condensing passage 413a is inclined with respect to both the arrangement direction X1 and the cooling air flow direction X2, so that the tube 41 is the same as that of the first embodiment. Such a horizontal blowing type boiling cooling device and a vertical blowing type boiling cooling device like this embodiment can be used in common.

(Other embodiments)
In addition, although the said 2nd Embodiment demonstrated the example which has arrange | positioned one heat radiating core part 4 to one outer wall surface 3a of the refrigerant tank 3, it is not restricted to this, and it radiates heat to the two outer wall surfaces 3a of the refrigerant tank 3. The core parts 4 may be arranged one by one.

It is a perspective view showing boiling cooling device 1 concerning a 1st embodiment. It is AA sectional drawing of FIG. It is a perspective view which shows the boiling cooling device 1 which concerns on 2nd Embodiment. It is a BB partial sectional view of FIG.

Explanation of symbols

3 Refrigerant tank 4 Radiating core part 41 Tube 410 Inner fin (condensation area increasing member)
411 Steam passage 412 Distribution passage 413 Condensing section 413a Condensing passage

Claims (2)

A refrigerant tank (3) for storing the refrigerant that boiled by receiving heat from the heating element (2);
The boiling cooling device includes a heat dissipation core section (4) for allowing the refrigerant that has boiled in the refrigerant tank (3) to flow in, heat exchange between the refrigerant and an external fluid, and condensing the refrigerant,
The heat dissipating core part (4) has a tube (41) that forms a refrigerant passage through which the refrigerant flows,
A condensation area increasing member (410) for increasing a heat transfer area with the refrigerant is provided inside the tube (41), and a condenser (413) for condensing the refrigerant boiled in the refrigerant tank (3). Is formed,
The inside of the condensing part (413) is divided into a plurality of condensing passages (413a) by the condensing area increasing member (410),
In the inside of the tube (41), the refrigerant excluding the condensing part (413) is disposed on the downstream side of the external fluid flow of the condensing part (413) and boiled in the refrigerant tank (3). And a distribution passage (412) for distributing the refrigerant from the vapor passage (411) to the plurality of condensation passages (413a),
The boiling cooling device characterized in that the steam passage (411) and the distribution passage (412) are each formed so that the passage cross-sectional area gradually decreases from the upstream side to the downstream side of the refrigerant flow. .   In the condensation area increasing member (410), the flow direction of the refrigerant in the condensation passage (413a) is inclined with respect to the arrangement direction (X1) of the refrigerant tank (3) and the heat radiating core (4). The boiling cooling device according to claim 1, wherein the boiling cooling device is disposed so as to be inclined with respect to a flow direction (X2) of the external fluid.

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