Cooling heat exchanger

Abstract

The present invention provides a novel cooling heat exchanger with a structure that allows for stable flow of the heat transfer medium in the cooling channel while efficiently generating a flow of the heat transfer medium over protrusions, thereby improving cooling performance. [Solution] A cooling heat exchanger is provided in which a cooling medium flows through a cooling channel 16 formed inside, and a cooling object 17 superimposed on a cooling surface 18 is cooled. The cooling channel 16 has projections 34 that protrude from the bottom surface of the cooling channel 16 to disturb the flow of the heat medium, and the projections 34 extend over the entire width of the cooling channel 16, with both ends of the projections 34 being connecting ends 54 that are continuous with the side walls of the cooling channel 16. The connecting ends 54 of the projections 34 are flow adjustment parts 56 that are recessed toward the bottom surface and extend in the direction of the length of the cooling channel 16.

Description

Technical Field

[0005]

[0001] The present invention relates to a cooling heat exchanger used for cooling a cooling target such as a battery pack used in an electrified vehicle, for example.

Background Art

[0002] For example, in electrified vehicles such as electric vehicles and hybrid vehicles, the amount of heat generated by a cooling target such as a battery pack has increased due to miniaturization and high performance, and the importance of cooling performance for the battery pack and the like has increased. As a cooling heat exchanger used for cooling a battery pack or the like, for example, a structure having a cooling flow path through which a cooling heat medium flows, as disclosed in US Patent No. 10,355,331 (Patent Document 1), has been conventionally proposed. In this cooling heat exchanger, the cooling surface is overlapped with a cooling target such as a battery pack, and the cooling target is cooled by the cooling surface being cooled by the heat medium flowing through the cooling flow path.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, forming such partial protrusions makes it easier for the heat transfer fluid to bypass the protrusions in the width direction of the cooling channel, suppressing the flow that goes over the protrusions. Also, the flow of the heat transfer fluid that bypasses the protrusions and passes between the protrusions and the side wall of the cooling channel becomes faster, which could cause the wall of the cooling channel, including the protrusions, to be eroded by the heat transfer fluid with a high flow velocity, potentially leading to problems such as leakage.

[0006] Fig. 11 of Patent Document 1 also shows a projection that extends continuously along the entire length of the cooling channel in the width direction. However, the heat transfer fluid flowing at both ends of the cooling channel in the width direction experiences greater flow resistance than the heat transfer fluid flowing in the middle of the channel due to the influence of the side walls of the cooling channel. Therefore, if a projection of a certain height, as in Patent Document 1, is formed along the entire length of the cooling channel in the width direction, it is conceivable that a local decrease in the flow velocity of the heat transfer fluid will occur at both ends of the channel in the width direction, hindering the flow of the heat transfer fluid or causing unintended vortices.

[0007] The problem to be solved by the present invention is to provide a novel cooling heat exchanger structure that can improve cooling performance by stably flowing the heat transfer medium in the cooling channel while efficiently generating a flow of the heat transfer medium over the protrusions. [Means for solving the problem]

[0008] The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is illustrative and can be combined with others as appropriate. Furthermore, the multiple components described in each embodiment can be recognized and adopted as independently as possible, and can be combined with any component described in another embodiment as appropriate. Thus, the present invention is not limited to the embodiments described below, and various other embodiments can be realized.

[0009] The first embodiment is a cooling heat exchanger for which a cooling medium flows through a cooling channel formed inside, and which cools an object to be cooled superimposed on a cooling surface, wherein the cooling channel is provided with a projection that protrudes from the bottom surface of the cooling channel to disturb the flow of the heat medium, the projection extends over the entire width of the cooling channel, and both ends of the projection are connected ends that are continuous with the side wall of the cooling channel, and the connected ends of the projection are flow regulating parts that are recessed toward the bottom surface and extend in the direction of the length of the cooling channel.

[0010] In a cooling heat exchanger with a structure according to this embodiment, the absence of a gap between the protrusion and the side wall of the cooling channel restricts the flow of the heat transfer medium through the gap, making it easier for the flow to overcome the protrusion. As a result, the turbulence-promoting effect (agitation of the heat transfer medium) by the protrusion is efficiently exerted.

[0011] The connecting ends that make up both ends of the protrusion are continuous with the side wall of the cooling channel, and no gap without a protrusion is formed between the protrusion and the side wall of the cooling channel. This prevents erosion of the channel wall surface due to fast flow through the gap, thus avoiding problems such as leakage.

[0012] Since the heat transfer fluid flowing through the ends of the flow channel near the side wall tends to experience greater flow resistance than the heat transfer fluid flowing through the intermediate section further away from the side wall, if a projection of the same height as the intermediate section is provided at the connection end to the side wall, the flow may be excessively restricted, potentially leading to poor heat transfer fluid flow at both ends of the cooling channel in the width direction. Therefore, by making the connection ends of the projections that are continuous with the side wall of the cooling channel into flow adjustment sections with a recessed shape toward the bottom, the height of the projections at both ends can be adjusted so that the heat transfer fluid flows appropriately, thereby improving and stabilizing cooling performance.

[0013] The second embodiment is a cooling heat exchanger described in the first embodiment, wherein the bottom of the concave flow control section is a curved surface.

[0014] According to the cooling heat exchanger structured in this embodiment, the bottom of the flow control section can be smoothly connected to the inner surface of the side wall of the cooling channel. In addition, the heat transfer medium that passes over the flow control section can flow more smoothly.

[0015] The third embodiment is a cooling heat exchanger described in the first or second embodiment, wherein the bottom of the flow control section is directly continuous with the protruding tip of the side wall section that protrudes from the bottom surface of the cooling channel.

[0016] In a cooling heat exchanger with a structure according to this embodiment, for example, the height of the connection end tends to be higher on the side where it connects to the side wall because the connecting end of the projection is continuous with the protruding tip of the side wall. However, because the connection end of the projection is a concave flow control section, it is possible to prevent the flow of the heat transfer medium from being excessively obstructed by the connection end of the projection.

[0017] The fourth embodiment is a cooling heat exchanger described in any one of the first to third embodiments, wherein the projection extends in the width direction of the cooling channel while being inclined in the length direction of the cooling channel.

[0018] Since the heat transfer fluid flowing through the cooling channel overcomes the protrusions in a direction approximately perpendicular to them, in the cooling heat exchanger according to this embodiment, where the protrusions extend at an inclination with respect to the flow direction of the cooling channel, which is the flow direction of the heat transfer fluid, the flow direction of the heat transfer fluid when it overcomes the protrusions is likely to be in the inclined direction with respect to the flow direction of the channel. As a result, the heat transfer fluid that overcomes the protrusions is more likely to experience a change in flow direction in the width direction of the channel, and turbulence in the flow of the heat transfer fluid can be generated more efficiently.

[0019] Furthermore, if the projection has an inclined shape as in this embodiment, the heat transfer medium tends to flow along the projection toward the end in the flow path width direction. In this case, for example, if the projection is formed over the entire width of the cooling flow path, and the height of the projection's end in the width direction (connecting end) is high, the heat transfer medium guided along the projection in the flow path width direction may flow into a dead-end corner formed at the connection between the connecting end of the projection and the side wall of the flow path. This can cause stagnation and turbulence of the heat transfer medium in the corner, potentially leading to a decrease in cooling performance due to obstruction of the heat transfer medium's flow. Therefore, by making the connecting end of the projection a concave flow control section, it is possible to make it less likely for unintended stagnation and turbulence of the heat transfer medium to occur at the end in the flow path width direction, and the cooling performance improvement effect caused by the heat transfer medium overcoming the projection can be effectively obtained. On the other hand, if there is a gap between both ends of the projection and the side wall of the flow path in the width direction of the flow path, for example, the guiding action of the heat transfer medium by the inclined projection may combine with the generation of a linear, high-speed flow section connecting the gap in the length direction of the flow path, which may reduce the heat exchange performance or cause problems with erosion of the side wall that forms the gap. In this embodiment, by providing a flow adjustment section between both ends of the projection and the side wall, it becomes possible to appropriately adjust the flow state of the heat transfer medium in such a gap, thereby mitigating or eliminating such problems.

[0020] The fifth embodiment is a cooling heat exchanger described in the fourth embodiment, wherein the projection extends inclined toward either the upstream or downstream side of the cooling channel toward both sides in the width direction of the cooling channel.

[0021] In a cooling heat exchanger with a structure according to this embodiment, the inclination directions of the parts on both sides of the protrusion are opposite to each other. As a result, the heat transfer medium that has passed over the parts on both sides of the protrusion either merges with each other downstream of the protrusion or separates with each other and flows toward the side wall. In either case, the flow direction of the heat transfer medium changes in the direction of the flow path width, which reduces the temperature difference of the heat transfer medium in the direction of the flow path width and improves the cooling performance by making the temperature of the heat transfer medium more uniform.

[0022] The sixth aspect is the cooling heat exchanger described in the fifth aspect, wherein the protrusion is V-shaped and extends obliquely toward the downstream side of the cooling flow path on both sides in the flow path width direction of the cooling flow path.

[0023] According to the cooling heat exchanger having the structure according to this aspect, since the protrusion is V-shaped and inclined toward the downstream side on both sides in the flow path width direction, the heat medium that has overcome both sides of the protrusion merges with each other on the downstream side of the protrusion. As a result, on the downstream side of the protrusion, the flow of the heat medium is disturbed or a vortex is formed, etc., and an improvement in the cooling performance due to the agitation of the heat medium is advantageously realized.

[0024] The seventh aspect is the cooling heat exchanger described in any one of the first to sixth aspects, wherein the width dimension of the flow regulating portion in the flow path width direction of the cooling flow path is within a range of 1 to 30% with respect to the width dimension of the protrusion in the flow path width direction of the cooling flow path.

[0025] According to the cooling heat exchanger having the structure according to this aspect, since the width dimension of the flow regulating portion is 1% or more with respect to the width dimension of the protrusion, an efficient flow of the heat medium by providing the flow regulating portion can be more effectively realized. Further, since the width dimension of the flow regulating portion is 30% or less with respect to the width dimension of the protrusion, an intermediate portion of the protrusion (a portion where the flow regulating portion is deviated inward in the flow path width direction) that can more advantageously agitate the heat medium can be provided with a sufficiently wide width.

Advantages of the Invention

[0026] According to the present invention, while stably flowing the heat medium in the cooling flow path, an efficient flow of the heat medium overcoming the protrusion can be generated, and the cooling performance of the cooling heat exchanger can be improved.

Brief Description of the Drawings

[0027] [Figure 1] Exploded perspective view of the cooling heat exchanger as the first embodiment of the present invention [Figure 2]This is a cross-sectional view of the cooling heat exchanger shown in Figure 1, which corresponds to the II-II cross-section in Figure 3. [Figure 3] Section III-III in Figure 2 [Figure 4] Figure 2 shows a magnified view of a portion of the IV-IV section. [Figure 5] Figure 3 shows an enlarged view of a portion of the VV cross-section. [Figure 6] A cross-sectional view showing a part of a cooling heat exchanger as a second embodiment of the present invention. [Modes for carrying out the invention]

[0028] Embodiments of the present invention will be described below with reference to the drawings.

[0029] Figures 1 to 3 show a cooling heat exchanger 10 as a first embodiment of the present invention. The cooling heat exchanger 10 has a structure in which an upper plate 12 and a lower plate 14 are stacked on top of each other and fixed together, and a cooling channel 16 through which a cooling heat transfer medium flows is formed inside. The cooling heat exchanger 10 cools the battery pack 17 by heat exchange between the heat transfer medium flowing through the cooling channel 16 and the battery pack 17, which is the object to be cooled and is stacked on the upper plate 12. In the following description, as a general rule, the vertical direction refers to the vertical direction in Figure 3, the left-right direction refers to the left-right direction in Figure 2, which is the direction of the length of the cooling channel 16, and the front-back direction refers to the vertical direction in Figure 2, which is the direction of the width of the cooling channel 16.

[0030] The upper plate 12 is shaped like a roughly rounded rectangular plate and is longer in the left-right direction than in the front-back direction. Preferably, the upper plate 12 is made of a material with high thermal conductivity, such as a metal such as iron or aluminum alloy, or a conductive synthetic resin mixed with conductive fillers such as metal particles. In this embodiment, the upper plate 12 is made of metal. The upper surface of the upper plate 12 is a cooling surface 18 on which the battery pack 17 is placed. The cooling surface 18 is a flat surface and extends perpendicular to the vertical direction. In this embodiment, the upper plate 12 has a roughly constant thickness throughout, and the upper surface (cooling surface 18) and the lower surface of the upper plate 12 are roughly parallel to each other.

[0031] The lower plate 14 is a roughly rounded rectangular plate that corresponds to the upper plate 12 when viewed in the vertical direction, and is longer in the horizontal direction than in the front-to-back direction. The lower plate 14 is made of a metal such as iron or aluminum alloy, or a synthetic resin. The lower plate 14 may be a molded product, but in this embodiment it is a pressed metal fitting.

[0032] The lower plate 14 has an outer peripheral fixing portion 20 that protrudes upward at its outer peripheral end. The outer peripheral fixing portion 20 has a roughly U-shape with an inverted cross-sectional shape, and its upper end surface has a flat portion that extends roughly parallel to the vertical direction. The flat portion of the upper end surface of the outer peripheral fixing portion 20 is superimposed on the lower surface of the outer peripheral end of the upper plate 12 and fixed by means of adhesive, welding, brazing, etc., thereby fixing the upper plate 12 and the lower plate 14 to each other at their outer peripheral ends.

[0033] The outer peripheral fixing portion 20 of the lower plate 14 and the upper plate 12 are liquid-tightly fixed together around their entire circumference. As a result, a liquid-sealed region 22 is formed on the inner side of the outer peripheral fixing portion 20 between the overlapping surfaces of the upper plate 12 and the lower plate 14, which is liquid-tightly separated from the external space.

[0034] Multiple partition walls 24 are provided in the middle portion of the lower plate 14 in the left-right direction. The partition walls 24 are provided so as to protrude upward, similar to the outer peripheral fixing portion 20. In this embodiment, the partition walls 24 have a roughly U-shape with the cross-section inverted vertically. The partition walls 24 extend linearly in the left-right direction. Both ends of the partition walls 24 are separated from the outer peripheral fixing portion 20 in the left-right direction. In this embodiment, four partition walls 24, 24, 24, 24 are arranged at roughly equal intervals in the front-rear direction within the liquid-sealed region 22. The left-right middle portion of the liquid-sealed region 22 is divided into five sections in the front-rear direction by the four partition walls 24, 24, 24, 24, and cooling passages 16 are formed between the front and rear sides of adjacent outer peripheral fixing portions 20 and the partition walls 24 in the flow path width direction, and between adjacent partition walls 24, 24 in the flow path width direction.

[0035] In this embodiment, the bottom wall of each cooling channel 16 is formed by the flat lower wall of the lower plate 14. The side walls on both sides in the width direction of each cooling channel 16 are formed by partition walls 24 and outer peripheral fixing parts 20 that rise from the bottom wall of the lower plate 14. Furthermore, the top wall of each cooling channel 16 is formed by the flat upper plate 12. That is, the upper end of each side wall is the protruding tip surface of the partition wall 24 or outer peripheral fixing part 20 that rises from the bottom wall of the lower plate 14 and overlaps with the upper plate 12.

[0036] The cooling channel 16 has its left end, which is upstream, connected to the inlet channel section 26. The inlet channel section 26 is located to the left of the partition wall section 24 and constitutes the left end of the liquid-sealed area 22. The inlet channel section 26 is not divided in the channel width direction by the partition wall section 24, and five cooling channels 16, 16, 16, 16, 16 branch off from the inlet channel section 26 and extend to the right. The inlet channel section 26 is provided with a supply port 28 that penetrates the lower wall of the lower plate 14, and the supply port 28 is connected to an external pipeline (not shown). When the cooling heat exchanger 10 is in operation, a low-temperature heat transfer medium is supplied from the external pipeline to the inlet channel section 26 through the supply port 28.

[0037] The cooling channel 16 has its right-hand end, which is downstream, connected to the outlet channel section 30. The outlet channel section 30 is located to the right of the partition wall section 24 and constitutes the right end of the liquid-sealed area 22. Similar to the inlet channel section 26, the outlet channel section 30 is not divided in the channel width direction by the partition wall section 24, and five cooling channels 16, 16, 16, 16, 16 merge in the outlet channel section 30. The outlet channel section 30 is provided with a discharge port 32 that penetrates the lower wall of the lower plate 14, and the discharge port 32 is connected to an external pipeline (not shown). When the cooling heat exchanger 10 is in operation, the heat transfer medium heated by heat exchange with the object to be cooled (described later) is discharged from the outlet channel section 30 to the external pipeline through the discharge port 32. The supply port 28 and the discharge port 32 are located diagonally opposite each other on the lower plate 14. Furthermore, the inlet-side flow channel section 26 and the outlet-side flow channel section 30 have approximately the same flow channel length and flow channel width dimensions.

[0038] Numerous protrusions 34 are formed in the cooling channel 16. The protrusions 34 are formed to project upward from the bottom surface 35 of the cooling channel 16. As shown in Figure 2, the protrusions 34 are roughly V-shaped when viewed from above. Specifically, the protrusions 34 have a pair of inclined portions 36, 36 that extend in the width direction of the cooling channel 16 while being inclined in the length direction of the channel, and the inclination directions of the pair of inclined portions 36, 36 are different from each other. The pair of inclined portions 36, 36 extend inclined to the right, which is the downstream side, from the center in the width direction of the cooling channel 16 outwards on both sides. The ridges 38 connecting the vertices of the cross-section of the protrusions 34 are shaped to extend in a V-shape when viewed from above.

[0039] Figure 4 shows an enlarged view of the cross-section of one projection 34 in the direction of the flow path length. In the cross-section shown in Figure 4, the projection 34 has a tapered cross-sectional shape that narrows towards the tip of the projection. More specifically, in the cross-section shown in Figure 4, the projection 34 has a cross-sectional shape that continuously comprises an arc-shaped projection top 40, an upstream inclined portion 44 that extends from the upstream end of the projection top 40 toward the projection base 42 (the lower end of the projection 34) and a downstream inclined portion 46 that extends from the downstream end of the projection top 40 toward the projection base 42. The cross-sectional shape of the projection 34 in the cross-section perpendicular to the ridge line 38 is approximately constant and is approximately the same as the cross-sectional shape in the direction of the flow path length at the front-to-back center shown in Figure 4.

[0040] In the cross-section shown in Figure 4, the radius of curvature R of the projection apex 40 including the ridge line 38 is set to be within the range of 0.05 to 1.5 times the length dimension L of the projection base 42 in the flow path direction, and more preferably within the range of 0.2 to 1.45 times. By setting the radius of curvature R of the projection apex 40 to be 0.05 times or more the length dimension L of the projection base 42, the projection apex 40 is made into a smooth arc-shaped cross-section without becoming a substantial corner. Furthermore, by setting the radius of curvature R of the projection apex 40 to be 1.5 times or less the length dimension L of the projection base 42, it is possible to prevent the length dimension of the projection 34 in the flow path direction from becoming excessively long, and to set the inclination angles α and β of the upstream inclined section 44 and downstream inclined section 46 that smoothly continue with the projection apex 40 to be sufficiently large.

[0041] The upstream inclined portion 44 may be curved, but in this embodiment it is linear. The upper end of the upstream inclined portion 44 extends tangentially to the projection top 40 from the upstream end of the projection top 40 and is smoothly continuous with the projection top 40 without any corners. The lower end of the upstream inclined portion 44 is curved in an arc and is smoothly continuous with the bottom surface 35 of the cooling channel 16 without any corners.

[0042] The upstream inclined section 44 has an inclination angle α with respect to the bottom surface 35 of the cooling channel 16 (bottom surface of the turbulence section 48) within the range of 20 to 70°, and more preferably within the range of 30 to 60°. When the upstream inclined section 44 is curved, the inclination angle α of the upstream inclined section 44 can be determined, for example, by taking the average value of the inclination angle of the upstream inclined section 44.

[0043] By setting the inclination angle α of the upstream inclined section 44 to 20° or more, the flow of the heat transfer medium from the upstream side toward the projection 34 is effectively disturbed by the upstream inclined section 44, which forms a sufficiently large angle with respect to the flow direction of the heat transfer medium, thereby improving the cooling performance through stirring. Furthermore, by setting the inclination angle α of the upstream inclined section 44 to 70° or less, it is possible to prevent the flow of the heat transfer medium from being excessively restricted by the projection 34.

[0044] The downstream inclined portion 46 may be curved, but in this embodiment it is linear. The upper end of the downstream inclined portion 46 extends tangentially from the downstream end of the projection top 40 and is smoothly continuous with respect to the projection top 40 without any corners. The lower end of the downstream inclined portion 46 is curved in an arc and is smoothly continuous with respect to the bottom surface 35 of the cooling channel 16 without any corners.

[0045] The downstream inclined section 46 has an inclination angle β with respect to the bottom surface 35 of the cooling channel 16 that is in the range of 20 to 70°, and more preferably in the range of 30 to 60°. When the downstream inclined section 46 is curved, the inclination angle β of the downstream inclined section 46 can be determined, for example, by taking the average value of the inclination angle of the downstream inclined section 46.

[0046] By setting the inclination angle β of the downstream inclined section 46 to 20° or more, the flow of the heat transfer medium overcoming the protrusion 34 is more likely to separate from the downstream inclined section 46, which is expected to have the effect of easily generating turbulent flows such as vortices on the downstream side of the protrusion 34. Furthermore, by setting the inclination angle β of the downstream inclined section 46 to 70° or less, the flow of the heat transfer medium along the downstream inclined section 46 is also ensured, and efficient stirring of the heat transfer medium can be expected through its merging with the flow that has separated from the downstream inclined section 46.

[0047] Multiple projections 34 of substantially the same shape and size are provided. In this embodiment, multiple projections 34 are arranged at predetermined intervals in the direction of the length of a single cooling channel 16. In this embodiment, the multiple projections 34 provided in a single cooling channel 16 are arranged at substantially constant intervals, but the intervals may change. For example, the intervals may become narrower as you move downstream, or they may become narrower towards a part of the middle of the length of the channel.

[0048] In this embodiment, the projection 34 is provided in the downstream portion (right side) of the cooling channel 16, but not in the upstream portion (left side). Therefore, the downstream portion of the cooling channel 16 is a turbulent flow section 48 where the projection 34 is provided, and the upstream portion of the cooling channel 16 is a laminar flow section 50 where the projection 34 is not provided. In this embodiment, as shown in Figure 2, the length dimension of the turbulent flow section 48 is larger than the length dimension of the laminar flow section 50. The length dimension of the turbulent flow section 48 is preferably in the range of 1.5 to 5 times, and more preferably in the range of 2 to 3 times, the length dimension of the laminar flow section 50. Note that the position of the turbulent flow section 48 is not necessarily limited to the downstream portion of the cooling channel 16; for example, it can be set in the central portion in the length direction of the cooling channel 16.

[0049] In the laminar flow section 50, the inner surface of the lower wall portion, which is composed of the lower plate 14, is an inclined surface 52 that slopes upward from the upstream side to the downstream side. As a result, in the laminar flow section 50, the cross-sectional area of ​​the cooling channel 16 decreases toward the downstream side. On the other hand, in the turbulent flow section 48, the cross-sectional area of ​​the channel in the portion away from the projection 34 is kept approximately constant along the length of the channel. Because the bottom surface of the laminar flow section 50 is an inclined surface 52, the depth dimension of the inlet channel portion 26 located upstream of the laminar flow section 50 is made larger than the depth dimension of the outlet channel portion 30 located downstream of the turbulent flow section 48. As a result, the volume of the inlet channel portion 26 is made larger than the volume of the outlet channel portion 30. Furthermore, in the outer peripheral fixing portion 20 and the partition wall portion 24, the protrusion height dimension from the bottom surface 35 of the cooling channel 16 that constitutes the side wall portion of the laminar flow section 50 of the cooling channel 16 gradually decreases toward the downstream side. Furthermore, the portion of the outer peripheral fixing portion 20 that constitutes the wall of the inlet-side flow path portion 26 has a larger protrusion height dimension from the bottom surface 35 of the cooling flow path 16 compared to the portion that constitutes the wall of the outlet-side flow path portion 30.

[0050] The protrusions 34 are provided in each of the five cooling channels 16, 16, 16, 16, 16. In this embodiment, the same number of protrusions 34 are provided at approximately the same intervals in each of the five cooling channels 16, 16, 16, 16, 16. In this embodiment, the position and range of the protrusions 34 in the length direction of the channel are also approximately the same in each of the five cooling channels 16, 16, 16, 16, 16. However, depending on, for example, the heat-generating part to be cooled, the formation positions of the protrusions 34 (positions of the turbulent flow section 48) in the five cooling channels 16, 16, 16, 16, 16 may differ from one another. Furthermore, the number, shape, size, and spacing of the protrusions 34 can be made different in each of the five cooling channels 16, 16, 16, 16, 16.

[0051] As shown in Figure 5, the projection 34 is provided continuously over the entire width of the cooling channel 16, and both ends are continuous with the side walls of the cooling channel 16, which are composed of the outer peripheral fixing portion 20 or the partition portion 24. That is, both ends of the projection 34 in the width of the cooling channel are connected ends 54 that are continuous with the outer peripheral fixing portion 20 or the partition portion 24. As can be seen from the fact that the projection 34 is provided from the bottom surface 35 of the cooling channel 16 to the middle in the depth direction, the projection 34 only needs to be provided continuously over the entire width of the cooling channel 16 on the bottom surface 35 side in the depth direction of the cooling channel 16 and have connecting ends 54.

[0052] As shown in Figure 5, the connecting end 54 is a flow control section 56 that extends in the direction of the flow path length of the cooling channel 16 and has a shape that is recessed downward toward the bottom surface 35 of the cooling channel 16. The flow control section 56 is composed of a curved surface with a concave shape at its bottom (top surface) and is smoothly and continuously connected to the inner surface of the side wall of the cooling channel 16 without any corners. At least a portion of the flow path width direction, the flow control section 56 is located on the bottom surface 35 side (below) of the cooling channel 16 than the ridge line 38 of the projection 34. The minimum height dimension h of the flow control section 56 relative to the bottom surface 35 of the cooling channel 16 is set to be in the range of 0.05 to 0.8 times the height dimension H of the projection 34 at the ridge line 38, and more preferably in the range of 0.1 to 0.5 times. In addition, the width dimension w1 of the flow control section 56 is smaller than the width dimension w2 of the intermediate part of the projection 34 that is detached from the flow control section 56. The width dimension w1 of the flow control section 56 is set to be within the range of 1 to 30% of the width dimension W of the projection 34, and more preferably within the range of 3 to 20%.

[0053] In this embodiment, the flow control section 56 has an inner portion in the flow path width direction that slopes linearly downward toward the outside in the flow path width direction, and an outer portion in the flow path width direction that is concave inward toward the bottom surface 35 of the cooling flow path 16. Furthermore, in this embodiment, the outer end of the flow control section 56 in the flow path width direction that is continuous with the side wall portion of the cooling flow path 16 is located above the end on the central side in the flow path width direction. The flow control section 56 extends linearly in the flow path length direction with a substantially constant cross-sectional shape.

[0054] The inner end of the flow control unit 56 in the flow path width direction is located inward in the flow path width direction relative to the radius radius of the corner connecting the side wall surface and the bottom surface 35 of the cooling flow path 16. In short, the flow control unit 56 extends in the flow path width direction up to the bottom surface 35 of the cooling flow path 16.

[0055] As shown in Figure 3, the cooling heat exchanger 10 with this structure is used with the battery pack 17, which is to be cooled, superimposed on the cooling surface 18 of the upper plate 12. Multiple battery packs 17 are arranged side by side in the left-right direction, which is the length direction of the cooling channel 16.

[0056] With the battery pack 17 placed on the cooling surface 18, a low-temperature heat transfer medium supplied from an external flow path (not shown) to the inlet-side flow path 26 flows through the cooling flow path 16, and the battery pack 17 is cooled by heat exchange between the heat transfer medium and the battery pack 17 via the upper plate 12. The heat transfer medium heated by heat exchange with the battery pack 17 is discharged from the outlet-side flow path 30 to an external flow path (not shown).

[0057] Due to heat exchange with the battery pack 17, the temperature of the heat transfer medium increases as it moves downstream. In this case, the portion of the heat transfer medium flowing through the upper part of the cooling channel 16, which is closer to the battery pack 17, becomes preferentially hotter. However, this reduces the temperature difference between the battery pack 17 and the heat transfer medium flowing through the upper part of the cooling channel 16, thus reducing the cooling performance. Therefore, in the cooling heat exchanger 10, protrusions 34 are provided in the cooling channel 16. When the heat transfer medium flows over the protrusions 34, the flow of the heat transfer medium is disturbed, and the heat transfer medium flowing through the upper part of the cooling channel 16 is mixed with the heat transfer medium flowing through the lower part. As a result, the temperature of the heat transfer medium flowing through the upper part of the cooling channel 16 decreases, and the temperature difference between the heat transfer medium flowing through the upper part and the battery pack 17 increases. This allows for efficient heat exchange between the heat transfer medium and the battery pack 17, enabling more effective cooling of the battery pack 17. In short, efficient cooling of the battery pack 17 is possible by utilizing not only the heat capacity of the heat transfer medium flowing through the upper part of the cooling channel 16, but also the total heat capacity of the heat transfer medium flowing through the cooling channel 16.

[0058] As the heat transfer medium flows through the upper part of the cooling channel 16, its temperature increases due to heat exchange with the battery pack 17 as it moves downstream of the cooling channel 16. This makes it easy for the temperature difference between the upper and lower parts of the heat transfer medium to become large downstream of the cooling channel 16. Therefore, in this embodiment, the cooling heat exchanger 10 has a turbulent flow section 48 with protrusions 34 in the downstream part of the cooling channel 16. As a result, in the downstream part of the cooling channel 16, where the high temperature of the upper part of the heat transfer medium affects the cooling performance, the protrusions 34 exert a stirring effect on the heat transfer medium, thereby reducing or eliminating the vertical temperature difference within the cooling channel 16 and suppressing the high temperature of the upper part of the heat transfer medium.

[0059] In this embodiment, the cooling heat exchanger 10 has a laminar flow section 50 without protrusions 34 in the upstream portion of the cooling channel 16. As a result, in the upstream portion of the cooling channel 16, where high temperatures at the top of the heat transfer medium are less likely to be a problem, turbulence in the flow of the heat transfer medium caused by the presence of protrusions 34 is suppressed, and the heat transfer medium is able to flow more smoothly. The bottom surface of the laminar flow section 50 in this embodiment is an inclined surface 52 that slopes with respect to the bottom surface of the turbulent flow section 48, and the cross-sectional area of ​​the cooling channel 16 gradually decreases toward the downstream side in the laminar flow section 50. Therefore, the heat transfer medium flowing through the laminar flow section 50 is less likely to decelerate toward the downstream side, and smoother flow of the heat transfer medium is achieved more effectively. As a result, it becomes possible to circulate the heat transfer medium using a less expensive pump with lower performance.

[0060] As shown in Figure 2, the projection 34 has a V-shape when viewed from above, becoming narrower towards the upstream side. The heat transfer fluid that crosses each inclined portion 36 of the projection 34 in a direction approximately perpendicular to the ridge line 38 merges with each other downstream of the projection 34, causing the flow to be strongly disturbed and, in some cases, forming a vortex flow, thus stirring the heat transfer fluid more efficiently.

[0061] As shown in Figure 5, the projections 34 are continuously provided along the entire width of the cooling channel 16, and the connecting ends 54, 54 at both ends are connected to the side walls of the cooling channel 16. This prevents the formation of a flow of the heat transfer medium that bypasses the projections 34 in the width of the channel, and allows the stirring action of the heat transfer medium caused by crossing over the projections 34 to be efficiently exerted.

[0062] Incidentally, the heat transfer medium flowing at both ends of the cooling channel 16 in the width direction experiences greater flow resistance due to its proximity to the side walls of the cooling channel 16, making it prone to flow turbulence or stagnation. Therefore, the cooling heat exchanger 10 has flow adjustment sections 56 at the connecting ends 54 that make up both ends of the projections 34, which are recessed downwards. As a result, the flow resistance exerted on the heat transfer medium by the formation of the projections 34 is smaller at both ends of the projections 34 than in the middle portion of the projections 34. Therefore, even if resistance from the side walls of the cooling channel 16 acts on the heat transfer medium flowing at both ends of the cooling channel 16 in the width direction, the flow of the heat transfer medium is not excessively hindered by the projections 34, and stable flow of the heat transfer medium in the cooling channel 16 is achieved.

[0063] In this embodiment, the flow control unit 56 has a smaller height from the bottom surface 35 on both outer sides in the flow path width direction, which are the connection side with the side wall of the cooling flow path 16, than on the central side in the flow path width direction. Therefore, the flow resistance caused by the protrusions 34 is further suppressed in the portion closer to the side wall of the cooling flow path 16, resulting in smoother flow of the heat transfer medium.

[0064] The minimum height dimension h of the flow control section 56 relative to the bottom surface 35 of the cooling channel 16 is set to be within the range of 0.05 to 0.8 times the height dimension H of the projection 34 on the ridge line 38, and more preferably within the range of 0.1 to 0.5 times. By setting the minimum height dimension h of the flow control section 56 to 0.05 times or more the height dimension H of the projection 34 on the ridge line 38, the stirring action of the heat transfer medium is effectively exerted even in the heat transfer medium that flows over the flow control section 56. Furthermore, by setting the minimum height dimension h of the flow control section 56 to 0.8 times or less the height dimension H of the projection 34 on the ridge line 38, the flow of the heat transfer medium over the flow control section 56 becomes smooth, and turbulence and stagnation of the heat transfer medium flow due to excessive flow resistance are effectively suppressed.

[0065] The flow control section 56 has a width dimension w1, which is the width dimension of the cooling channel 16, that is smaller than the width dimension w2 of the intermediate portion of the projection 34 that is not adjacent to the flow control section 56. Preferably, the width dimension w1 of the flow control section 56 is in the range of 1 to 30% of the width dimension W of the projection 34, and more preferably in the range of 3 to 20%. As a result, the flow control section 56, which is partially provided near the side wall of the cooling channel 16, enables smooth flow of the heat transfer medium at the end of the cooling channel 16 in the width direction of the channel, while ensuring sufficient width dimension w2 of the intermediate portion of the projection 34, which has a large protrusion height from the bottom surface 35, thereby efficiently obtaining the stirring action of the heat transfer medium by the projection 34.

[0066] Figure 6 shows a part of a cooling heat exchanger 70 as a second embodiment of the present invention. The cooling heat exchanger 70 has a structure in which protrusions 72 are formed in the cooling channel 16. In the following description, components and parts that are substantially the same as those in the first embodiment will be denoted by the same reference numerals in the figures and their description will be omitted. Furthermore, since the structure of the protrusions 72 described below differs from that of the cooling heat exchanger 10 of the first embodiment, the structure of other parts can be described by referring to the first embodiment.

[0067] The projection 72 in this embodiment, like the projection 34 in the first embodiment, is V-shaped when viewed from above and narrows in the front-to-back direction toward the upstream. As shown in Figure 6, the projection 72 is continuously provided along the entire width of the cooling channel 16, and both ends are connected ends 74 that are continuous with the side walls of the cooling channel 16.

[0068] The connecting end 74 of the projection 72 is a flow control section 76 that is recessed toward the bottom surface 35 of the cooling channel 16. In this embodiment, the outer end of the flow control section 76 in the flow channel width direction is continuous with the upper end, which is the protruding tip of the side wall portion (outer peripheral fixing portion 20 and partition wall portion 24 in Figure 6) that protrudes from the bottom surface 35 of the cooling channel 16. Therefore, the outer end of the flow control section 76 in the flow channel width direction is located above the ridge line 38 of the projection 72. The flow control section 76 is located below the ridge line 38 in the middle portion in the flow channel width direction, and the minimum height dimension h' from the bottom surface 35 of the cooling channel 16 is smaller than the height dimension H of the projection 72 at the ridge line 38. Furthermore, the minimum height dimension h' of the flow control section 76 in the projection 72 in this embodiment is larger than the minimum height dimension h of the flow control section 56 in the projection 34 in the first embodiment, and the difference with respect to the height dimension H of the projection 72 at the ridge line 38 is smaller than in the first embodiment.

[0069] The cooling heat exchanger 70, structured according to this embodiment, is used to cool objects such as battery packs, similar to the cooling heat exchanger 10 of the first embodiment. And, similar to the first embodiment, effective cooling performance can be obtained even further downstream of the cooling channel 16 based on the stirring action of the heat transfer medium by the protrusions 72.

[0070] In this embodiment, the outer end of the flow control unit 76 in the flow path width direction is continuous with the upper end of the side wall of the cooling flow path 16. As a result, for example, as shown in Figure 6, when the side wall of the cooling flow path 16 has an inclined shape due to curvature, the projection 72 is provided over a wider area in the flow path width direction, thereby more advantageously obtaining the stirring action of the heat transfer medium by the projection 72.

[0071] Furthermore, if both ends of the projection 72 in the flow path width direction (connecting ends 74, 74) are continuous with the upper end of the side wall of the cooling flow path 16, the height of the connecting ends 74, 74 of the projection 72 tends to be higher than that of the middle portion of the projection 72. Therefore, by making the connecting ends 74, 74 of the projection 72 into concave flow adjustment portions 76, it is possible to prevent the connecting ends 74, 74 from becoming excessively high, even if the connecting ends 74, 74 of the projection 72 are continuous with the upper end of the side wall of the cooling flow path 16.

[0072] While embodiments of the present invention have been described in detail above, the present invention is not limited by its specific description. For example, the lower plate is preferably a pressed metal fitting, but may also be a molded product. The molded lower plate is not limited to metal, and can be made of synthetic resin containing a thermal conductive filler, for example. The upper plate is preferably made of metal with high thermal conductivity, but can also be made of synthetic resin containing a thermal conductive filler, for example.

[0073] The shape and size of the upper and lower plates when viewed from above are not particularly limited and can be appropriately changed, for example, depending on the space available for the installation of the cooling heat exchanger in the vehicle.

[0074] In the first embodiment, a structure was illustrated in which a liquid-sealed region 22 (cooling channel 16) is formed between the overlapping surfaces of a separate upper plate 12 and lower plate 14. However, the members constituting the wall portion of such a liquid-sealed region are not limited to the separate upper plate and lower plate. Specifically, for example, a liquid-sealed region (cooling channel) can also be formed inside a cylindrical member by closing the openings on both axial sides of the cylindrical member with lid members.

[0075] The number, size (length, width, and depth of the cooling channels), and arrangement of the cooling channels can be changed as appropriate. The shape of the cooling channels is not limited to a straight-line shape as in the first embodiment, but may also be curved or bent in the direction of the channel width.

[0076] The projection is not necessarily limited to a V-shape, and can take on various shapes, such as an inverted V-shape that widens toward the upstream side, a W-shape or inverted W-shape formed by arranging two V-shapes or inverted V-shapes in the direction of the channel width, a zigzag shape formed by arranging three or more V-shapes or inverted V-shapes in the direction of the channel width, an inclined straight line that slopes in one direction toward the upstream or downstream side in the direction of the channel width, a non-inclined straight line that extends in the direction of the channel width without sloping in the direction of the channel length, a curved shape such as a semi-circular arc, or a wave shape that extends in the direction of the channel width while meandering.

[0077] The cross-sectional shape perpendicular to the ridge of the projection is not limited to the mountain shape shown in the first embodiment, which has a small-diameter arc-shaped projection top 40, an upstream inclined portion 44, and a downstream inclined portion 46. Specifically, for example, the projection top may be an arc shape with a larger radius of curvature, and the upstream and downstream ends of the projection top may be smoothly connected to the bottom surface of the cooling channel with curved surfaces. Alternatively, for example, the projection may not have an arc-shaped projection top, and the protruding tip may be sharp in a cross-section perpendicular to the ridge.

[0078] The inclined portion of the projection may have a varying height in the inner portion in the flow path width direction, away from the connecting end (flow adjustment portion). Specifically, for example, the projection may have a low projection at one end in the flow path width direction, where the height from the bottom surface of the cooling flow path is small, and a high projection at the other end in the flow path width direction, where the height from the bottom surface of the cooling flow path is large. Alternatively, for example, a central low projection, where the height from the bottom surface of the cooling flow path is lower towards the center in the flow path width direction, and a central high projection, where the height from the bottom surface of the cooling flow path is higher towards the center in the flow path width direction, may be arranged alternately along the length of the flow path, thereby enabling efficient stirring of the heat transfer medium.

[0079] Multiple protrusions arranged along the length of a cooling channel may have varying heights. Specifically, for example, the height of multiple protrusions arranged along the length of a cooling channel may gradually increase toward the downstream side of the cooling channel. This allows for a stronger stirring effect of the heat transfer medium by the protrusions in the turbulent flow section where the protrusions are formed, as one moves downstream. Alternatively, for example, the height of multiple protrusions arranged along the length of a cooling channel may gradually increase toward the center of the cooling channel, allowing for efficient cooling of objects where the center of the cooling channel becomes hotter. Furthermore, when multiple cooling channels are provided in parallel, a cooling channel located in the center of the channel width direction may have more protrusions than cooling channels located at both ends of the channel width direction. This can reduce the difference in cooling performance between a cooling channel located in the center of the channel width direction, where cooling by outside air is unlikely, and cooling channels located at both ends of the channel width direction, where cooling by outside air can be expected.

[0080] The multiple protrusions arranged along the length of the cooling channel may have varying spacing between adjacent protrusions along that length. Setting the spacing between adjacent protrusions in the length of the cooling channel narrows the flow of the heat transfer medium, making it more turbulent and improving the cooling performance through stirring of the heat transfer medium. Conversely, setting the spacing between adjacent protrusions in the length of the cooling channel widens the flow of the heat transfer medium.

[0081] The flow control portion of the projection only needs to be concave toward the bottom surface of the cooling channel, and its upper surface (bottom) does not necessarily need to be curved. In other words, the upper surface of the flow control portion can be linear; for example, the upper surface of the flow control portion may be V-shaped when viewed in the direction of the length of the channel, or it may be a flat surface that extends approximately perpendicular to the vertical direction.

[0082] For example, the structure of the present invention can also be applied to a cooling heat exchanger with a double-sided cooling structure, in which both the upper surface of the upper plate and the lower surface of the lower plate are cooling surfaces, and inner fins are arranged between the opposing surfaces of the upper and lower plates to divide the liquid-sealed area into upper and lower halves. In a cooling heat exchanger with a double-sided cooling structure, if the inner fins constitute the bottom wall and side wall of the cooling channel, the projections equipped with flow control sections are formed on the inner fins. [Explanation of Symbols]

[0083] 10. Cooling heat exchanger (first embodiment) 12 Upper Plate 14 Lower Plate 16 Cooling channel 17. Battery pack (to be cooled) 18 Cooling surface 20 Outer peripheral fixing portion 22 Liquid seal area 24 Bulkhead 26 Inlet side channel section 28 supply ports 30 Outlet side flow path section 32 discharge ports 34 Protrusion 35 Bottom 36 Slope 38 Ridge 40 Top of protrusion 42 Protrusion base 44 Upstream slope 46 Downstream slope 48 Turbulence section 50 Laminar flow section 52 Slope 54 Connection end 56 Flow adjustment section 70 Cooling heat exchanger (second embodiment) 72 Protrusion 74 Connection End 76 Flow adjustment section R Radius of curvature of the projection apex L-shaped projection base length dimension α Inclination angle of the upstream inclined section β Inclination angle of the downstream inclined section h,h' Minimum height dimension of the flow control section Height dimension of the protrusion on the H ridge w1 Width dimension of the flow control section w2 Width dimension of the intermediate part of the protrusion detached from the flow control section W (width dimension of the protrusion)

Claims

1. A cooling heat exchanger having a cooling channel formed inside through which a cooling heat transfer medium flows, for cooling an object to be cooled superimposed on a cooling surface, The cooling channel is provided with protrusions that obstruct the flow of the heat transfer medium, which protrude from the bottom surface of the cooling channel. The projection extends across the entire width of the cooling channel, and both ends of the projection are connected to the side walls of the cooling channel. A cooling heat exchanger in which the connecting end of the projection is a flow control section that extends in the direction of the flow path length of the cooling channel with a recessed shape toward the bottom surface.

2. The cooling heat exchanger according to claim 1, wherein the bottom of the concave flow control section is a curved surface.

3. The cooling heat exchanger according to claim 1 or 2, wherein the bottom of the flow control section is directly continuous with the protruding tip of the side wall section that protrudes from the bottom surface of the cooling channel.

4. The cooling heat exchanger according to claim 1 or 2, wherein the projection extends in the width direction of the cooling channel while being inclined in the length direction of the cooling channel.

5. The cooling heat exchanger according to claim 4, wherein the projection extends toward both sides in the width direction of the cooling channel and is inclined toward either the upstream or downstream side of the cooling channel.

6. The cooling heat exchanger according to claim 5, wherein the projection is V-shaped and extends inclined toward the downstream side of the cooling channel toward both sides in the width direction of the cooling channel.

7. The cooling heat exchanger according to claim 1 or 2, wherein the width dimension of the flow control portion in the flow width direction of the cooling channel is within the range of 1 to 30% of the width dimension of the projection in the flow width direction of the cooling channel.

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