EGR cooler and vehicle waste heat recovery device

Abstract

An EGR cooler (1) performs heat exchange between exhaust gas and cooling water via a tube, by causing the exhaust gas to flow through the tube. The EGR cooler (1) includes a gas inlet part (20), a gas outlet part, a water inlet part, and a water outlet part (50). The water outlet part (50) includes: a body section (53) that forms a water outlet passage (52) through which the cooling water passes; and a blocking section (54) that extends from the body section (53) on the side closer to the water inlet part than the water outlet passage (52), in a direction in which the blocking section moves farther away from the water inlet part.

Description

Technical Field

[0001] The present disclosure relates to an EGR cooler and a waste heat recovery device for a vehicle.

Background Art

[0002] An EGR cooler for cooling exhaust gas of an automobile or the like is known from Patent Document 1 or the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The EGR cooler described in Patent Document 1 enhances the cooling efficiency by uniformly circulating cooling water on the outer surface side of a flat tube through which exhaust gas passes at the inlet of the cooling water. By the way, although the cooling efficiency near the inlet of the cooling water can be enhanced by the structure of Patent Document 1, there is room for improvement in terms of enhancing the cooling efficiency of the entire EGR cooler.

[0005] Therefore, the present disclosure provides an EGR cooler and a waste heat recovery device for a vehicle with enhanced overall cooling efficiency.

Means for Solving the Problems

[0006] The EGR cooler according to one aspect of the present disclosure is a plurality of tubes through which exhaust gas flows inside, and a casing that houses the tubes, an EGR cooler that performs heat exchange between the exhaust gas and the cooling water through the tubes by flowing the cooling water in the casing, the EGR cooler A gas inlet portion for introducing the exhaust gas into the tube, A gas outlet portion for discharging the exhaust gas from the tube, A water inlet portion for introducing the cooling water into the casing, A water outlet portion for discharging the cooling water from the casing, and has, The water outlet portion, A main body portion forming a water outlet passage through which the cooling water passes, A blocking portion extending in a direction away from the water inlet portion from the main body portion on a side closer to the water inlet portion than the water outlet passage.

[0007] The waste heat recovery device for a vehicle according to one aspect of the present disclosure, A plurality of tubes through which exhaust gas flows inside, and a casing housing the tubes, A waste heat recovery device for a vehicle that performs heat exchange between the exhaust gas and the cooling water through the tubes by flowing the cooling water in the casing, The waste heat recovery device for a vehicle, A gas inlet portion for introducing the exhaust gas into the tube, A gas outlet portion for discharging the exhaust gas from the tube, A water inlet portion for introducing the cooling water into the casing, A water outlet portion for discharging the cooling water from the casing, and has, The water outlet portion, A main body portion forming a water outlet passage through which the cooling water passes, A blocking portion extending in a direction away from the water inlet portion from the main body portion on a side closer to the water inlet portion than the water outlet passage.

[0008] According to the present disclosure, an EGR cooler and a waste heat recovery device for a vehicle with enhanced overall cooling efficiency are provided.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. For members having the same reference numerals as those already described in the description of the embodiments, for the sake of convenience of explanation, the description thereof will be omitted. Also, the dimensions of each member shown in these drawings may be different from the actual dimensions of each member for the sake of convenience of explanation.

[0011] In the description of the present embodiment, for the sake of convenience of explanation, the "left-right direction", "front-back direction", and "up-down direction" will be referred to as appropriate. Here, the "up-down direction" is a direction including the "upward direction" and the "downward direction". The "front-back direction" is a direction including the "front direction" and the "rear direction". The "left-right direction" is a direction including the "left direction" and the "right direction". In the figures described hereinafter, the symbol U indicates the upward direction. The symbol D indicates the downward direction. The symbol F indicates the front direction. The symbol B indicates the rear direction. The symbol L indicates the left direction. The symbol R indicates the right direction. Note that these directions do not necessarily coincide with the respective directions set for the vehicle when the EGR cooler is attached to the vehicle.

[0012] FIG. 1 is a perspective view of an EGR cooler 1 according to an embodiment of the present disclosure. As shown in FIG. 1, the EGR cooler 1 includes a heat exchange section 10, a gas inlet section 20 for introducing exhaust gas into the heat exchange section 10, a gas outlet section 30 for discharging exhaust gas from the heat exchange section 10, a water inlet section 40 for introducing cooling water into the heat exchange section 10, and a water outlet section 50 (see FIG. 2) for discharging cooling water from the heat exchange section 10.

[0013] In the example shown in FIG. 1, hot exhaust gas flows into the heat exchange section 10 through the gas inlet section 20 from the front, heat exchange is performed with the cooling water inside the heat exchange section 10, and the cooled exhaust gas is discharged rearward from the heat exchange section 10 through the gas outlet section 30. Also, cold cooling water flows into the heat exchange section 10 through the water inlet section 40 at the rear of the heat exchange section 10 from below, heat exchange is performed with the exhaust gas inside the heat exchange section 10, and the heated cooling water is discharged downward through the water outlet section 50 at the front of the heat exchange section 10. The illustrated EGR cooler 1 is a so-called counterflow type EGR cooler in which the flow direction of the exhaust gas and the flow direction of the cooling water face each other in the heat exchange section 10.

[0014] FIG. 2 is an exploded perspective view of the EGR cooler 1. As shown in FIG. 2, the heat exchange section 10 includes a plurality of tubes 11 and a casing 12 that houses these tubes 11. The tube 11 is a flat hollow plate-like member that is long in the front-rear direction. The exhaust gas flows inside the tube 11. The cooling water flows in the space between the tubes 11 inside the casing 12. Fins 17 are provided inside the tube 11 to assist in heat exchange between the exhaust gas and the cooling water. Dimples 13 that cause turbulent flow in the cooling water to promote heat exchange are provided on the outer surface of the tube 11.

[0015] The casing 12 is a long rectangular tubular member in the front-rear direction. A front end plate 14 is attached to the front end of the casing 12. A rear end plate 15 is attached to the rear end of the casing 12. The gas inlet portion 20 is attached to the casing 12 via the front end plate 14. The gas outlet portion 30 is attached to the casing 12 via the rear end plate 15. The tube 11 is attached to these front end plate 14 and rear end plate 15.

[0016] Figure 3 is a cross-sectional view of the EGR cooler 1 as seen from above. Figure 4 is a cross-sectional view taken along the IV-IV section of Figure 3. As shown in Figures 3 and 4, the plurality of tubes 11 are arranged in the left-right direction within the casing 12. An opening 14a is provided at a position corresponding to the opening of the tube 11 in the front end plate 14, and the exhaust gas can be taken into the tube 11. An opening is provided at a position corresponding to the opening of the tube 11 in the rear end plate 15, and the exhaust gas can be discharged from the tube 11 to the outside. The space between the openings 14a of the front end plate 14 and the space between the openings of the rear end plate 15 are closed, and a sealed space is formed between the casing 12, the tube 11, the front end plate 14, and the rear end plate 15. The cooling water flows through this sealed space.

[0017] Figure 5 is a cross-sectional view taken along the V-V section of Figure 3. In the present embodiment, a water inlet portion 40 and a water outlet portion 50 are provided on the lower surface of the casing 12. Figure 6 is an enlarged view of the VI portion of Figure 5. As shown in Figure 6, in the present embodiment, the water outlet portion 50 is formed as an adapter 51 attached to the casing 12. This adapter 51 includes a main body portion 53 that forms a water outlet passage 52 through which the cooling water passes, and a blocking portion 54 that extends from the main body portion 53 closer to the water inlet portion 40 than the water outlet passage 52 in a direction away from the water inlet portion 40.

[0018] Incidentally, generally, a fluid tends to flow from the inlet to the outlet along the shortest path. Therefore, unlike the present embodiment, when there is no blocking portion and the cooling water flows linearly from the water inlet portion to the water outlet portion, the cooling water tends to stagnate in the vicinity of the upper front region inside the casing. If the cooling water stagnates, heat exchange between the cooling water and the exhaust gas hardly progresses in this region, and it is difficult to enhance the cooling efficiency of the entire EGR cooler. However, according to the EGR cooler 1 according to the present embodiment, the water outlet portion 50 is provided with a blocking portion 54 that extends in a direction away from the water inlet portion 40 from the main body portion 53 closer to the water inlet portion 40 than the water outlet passage 52. For this reason, the blocking portion 54 blocks the flow of the cooling water that attempts to flow directly from the water inlet portion 40 to the water outlet portion 50. As shown in FIG. 6, the cooling water Y1 blocked by the blocking portion 54 wraps around along the blocking portion 54 to a position in front of the water outlet passage 52, hits the front end plate 14 and changes its direction downward, and then hits the lower surface of the casing 12 and changes its direction forward, and is then discharged to the outside through the water outlet passage 52. The cooling water Y1 that flows around the blocking portion 54 in this way entrains and flows the cooling water Y2 in the vicinity of the upper front region A inside the casing 12. Therefore, by providing the blocking portion 54, the cooling water can flow widely inside the casing 12. As a result, a flow of the cooling water is also generated in the upper front region A, which is a "portion where the cooling water tends to stagnate" far from the water inlet portion 40 and the water outlet portion 50 inside the casing 12, and the exhaust gas can be cooled using a portion where the contribution degree of heat exchange was conventionally low, and the cooling efficiency of the entire EGR cooler 1 is enhanced.

[0019] In the EGR cooler 1 of the present embodiment, the water outlet portion 50 is provided at a position closer to the gas inlet portion 20 than the water inlet portion 40, and the blocking portion 54 extends toward the gas inlet portion 20. That is, the EGR cooler 1 of the present embodiment is of a counterflow type. In the case of such a counterflow type EGR cooler 1, hot exhaust gas that has not been cooled blows against the tube 11 near the gas inlet portion 20. For this reason, the tube 11 near the gas inlet portion 20 tends to become hot. In the EGR cooler 1 of the present embodiment, the portion of the tube 11 that tends to become hot can be cooled by the cooling water that flows around to near the gas inlet portion 20 by the blocking portion 54 that extends toward the gas inlet portion 20. For this reason, the present embodiment is suitable for the counterflow type EGR cooler 1.

[0020] FIG. 7 is a perspective view of the adapter 51. As shown in FIG. 7, a standing wall portion 55 that extends upward and an extension wall portion 56 are provided on the upper surface 53a of the main body portion 53 of the adapter 51. The standing wall portion 55 is a portion that extends in the left-right direction. The extension wall portion 56 is a portion that extends forward from the right end and the left end of the standing wall portion 55. The standing wall portion 55 blocks the cooling water that flows along the lower surface of the casing 12 from the water inlet portion 40 and changes the flow upward. The extension wall portion 56 blocks the cooling water that flows from the rear to the front from flowing into the water outlet passage 52 from the left and right sides of the standing wall portion 55.

[0021] The blocking portion 54 is provided on the upper surfaces of the standing wall portion 55 and the extension wall portion 56. The blocking portion 54 is plate-shaped and extends in the front-rear direction and the left-right direction. The blocking portion 54 is a substantially rectangular portion that is long in the left-right direction. Among the front ends (tips) of the blocking portion 54, the central portion 54a in the left-right direction extends the longest on the side opposite to the water inlet portion 40, and both end portions 54b in the left-right direction are shorter than the central portion 54a. The front end of the blocking portion 54 extends to a position that covers at least a part of the water outlet passage 52.

[0022] As shown in FIG. 7, in the EGR cooler 1 of the present embodiment, the water outlet portion 50 includes a standing wall portion 55 that protrudes from the main body portion 53 closer to the water inlet portion 40 than the water outlet passage 52 into the casing 12, and a blocking portion 54 that extends from the tip of the standing wall portion 55 in a direction away from the water inlet portion 40. According to such a configuration, the cooling water can be made to flow around to a part far from the water outlet portion 50 by the vertical wall portion 55 and the blocking portion 54, and the cooling water can be made to flow more widely throughout the casing 12. Thereby, an EGR cooler 1 with higher cooling efficiency can be realized.

[0023] Also, in the EGR cooler 1 of the present embodiment as shown in FIG. 7, the water outlet portion 50 has a vertical wall portion 55 and an extension wall portion 56. The vertical wall portion 55 protrudes from the main body portion 53 closer to the water inlet portion 40 than the water outlet passage 52 into the casing 12, and extends so as to block the space between the water inlet portion 40 and the water outlet passage 52. The extension wall portion 56 extends from both ends of the vertical wall portion 55 in a direction away from the water inlet portion 40. According to such a configuration, the blocking portion 54 can make the cooling water flow in a direction away from the lower surface of the casing 12, and the extension wall portion 56 can make the cooling water flow in a direction away from the water outlet portion 50. Thereby, the cooling water can be made to flow around in a wider range, and the cooling water can be made to flow more widely throughout the casing 12. Thereby, an EGR cooler 1 with higher cooling efficiency can be realized.

[0024] Also, in the EGR cooler 1 of the present embodiment as shown in FIGS. 6 and 7, the blocking portion 54 is provided inside the casing 12. Compared with the case where the blocking portion 54 is provided outside the casing 12, the EGR cooler 1 can be configured to be smaller.

[0025] Also, in the EGR cooler 1 of the present embodiment as shown in FIGS. 6 and 7, the blocking portion 54 extends into the space between the inner surface of the casing 12 and the tube 11. According to such a configuration, the cooling water flowing along the lower surface of the casing 12 from the water inlet portion 40 can be made to flow toward the tube 11 that is performing heat exchange, and the cooling efficiency can be further enhanced.

[0026] Furthermore, as shown in FIG. 7, in the EGR cooler 1 of the present embodiment, a mounting hole 16 (see FIG. 6) is formed in the casing 12, and the main body portion 53 is mounted in the mounting hole 16. By separately preparing an adapter 51 having a complex shape including a blocking portion 54 and mounting this adapter 51 to the casing 12, the EGR cooler 1 can be easily assembled. Note that, unlike the present embodiment, the water outlet portion 50 including the blocking portion 54 may be integrally formed with the casing 12. For example, when the casing 12 is made of a metal such as aluminum, stainless steel, or copper, the water outlet portion 50 can be integrally provided with the casing 12 by drilling or pressing.

[0027] Furthermore, as shown in FIG. 7, in the EGR cooler 1 of the present embodiment, the blocking portion 54 extends so as to face the water outlet passage 52. The tip of the blocking portion 54 has a central portion 54a corresponding to the water outlet passage 52 extending further to the side opposite to the water inlet portion 40 than its end portion 54b. Generally, in the cross section shown in FIG. 3, the flow rate of the cooling water flowing in the central region in the left - right direction in the casing 12 is larger than the flow rate of the cooling water flowing in its left region and right region. By the central portion 54a at the tip of the blocking portion 54 extending the longest to the side opposite to the water inlet portion 40, it becomes difficult for the cooling water in the central region to flow, and it becomes easy for the cooling water in the left region and right region to flow, thereby making the flow of the cooling water in the casing 12 more uniform.

[0028] Note that the shape of the adapter 51 is not limited to the shape described in the above - mentioned embodiment. FIG. 8 is a top view showing an adapter 151 of an EGR cooler according to a first modification of the present disclosure. FIG. 9 is a top view showing an adapter 251 of an EGR cooler according to a second modification of the present disclosure. As shown in FIG. 8, the blocking portion 154 of the adapter 151 may have a shape combining a rectangle and a semicircle in a top view. A standing wall portion 155 is provided at the upper part of the figure, and a blocking portion 154 extending from the standing wall portion 155 toward the gas inlet portion 20 (below the figure) is provided. Also in this case, the central portion 154a in the left - right direction at the tip of the blocking portion 154 extends longer toward the gas inlet portion 20 than both end portions 154b. As shown in FIG. 9, the blocking portion 254 of the adapter 251 may have a trapezoidal shape in a top view. A standing wall portion 255 is provided at the upper part of the figure, and a blocking portion 254 extending from the standing wall portion 255 toward the gas inlet portion 20 (lower part of the figure) is provided. Also in this case, the central portion 254a in the left - right direction of the tip of the blocking portion 254 extends longer toward the gas inlet portion 20 than the end portion 254b.

[0029] In the above - described embodiment, an example in which the present disclosure is applied to an EGR cooler has been described. However, the present disclosure may be applied to a waste heat recovery device for a vehicle. A waste heat recovery device for a vehicle is a component mounted on a vehicle, also called a heat collector. The waste heat recovery device for a vehicle performs heat exchange between exhaust gas and cooling water, and is used, for example, to warm the engine with the warmed cooling water to improve fuel efficiency. Such a waste heat recovery device for a vehicle also includes a tube, a casing, etc., and can be configured in the same manner as the above - described configuration.

[0030] This application appropriately incorporates the content disclosed in the Japanese Patent Application (Japanese Patent Application No. 2020 - 183825) filed on November 2, 2020.

Explanation of Reference Numerals

[0031] 1 EGR cooler 10 Heat exchange portion 11 Tube 12 Casing 13 Dimple 14 Front end plate 15 Rear end plate 16 Mounting hole 20 Gas inlet portion 30 Gas outlet portion 40 Water inlet portion 50 Water outlet portion 51 Adapter 52 Water outlet passage 53 Main body portion 54 Blocking portion 55 Standing wall portion 56 Extension wall portion A Front - upper region

Claims

1. An EGR cooler having a plurality of tubes through which exhaust gas flows inside, and a casing that houses the tubes, wherein heat exchange is performed between the exhaust gas and the cooling water through the tubes by flowing the cooling water through the casing, the EGR cooler comprising: a gas inlet portion for introducing the exhaust gas into the tubes; a gas outlet portion for discharging the exhaust gas from the tubes; a water inlet portion for introducing the cooling water into the casing; a water outlet portion for discharging the cooling water from the casing, the water outlet portion comprising: a main body portion that forms a water outlet passage through which the cooling water passes; a blocking portion that extends in a direction away from the water inlet portion from the main body portion on a side closer to the water inlet portion than the water outlet passage; the blocking portion extending so as to face the water outlet passage; an EGR cooler in which a central portion corresponding to the water outlet passage of the tip of the blocking portion extends to the side opposite to the water inlet portion from its end portion.

2. The water outlet portion is provided at a position closer to the gas inlet portion than the water inlet portion, and the blocking portion extends toward the gas inlet portion. The EGR cooler according to claim 1.

3. The water outlet portion comprises: a standing wall portion that protrudes from the main body portion on a side closer to the water inlet portion than the water outlet passage toward the inside of the casing; and the blocking portion that extends in a direction away from the water inlet portion from the tip of the standing wall portion. The EGR cooler according to claim 1.

4. The water outlet portion comprises: a standing wall portion that protrudes from the main body portion on a side closer to the water inlet portion than the water outlet passage toward the inside of the casing and extends so as to block between the water inlet portion and the water outlet passage; and extension wall portions that extend in a direction away from the water inlet portion from both ends of the standing wall portion. The EGR cooler according to claim 1.

5. The EGR cooler according to claim 1, wherein the blocking portion is provided inside the casing.

6. The EGR cooler according to claim 1, wherein the blocking portion extends into a space between the inner surface of the casing and the tubes.

7. A mounting hole is formed in the casing, and the main body portion is mounted in the mounting hole. The EGR cooler according to claim 1.

8. An EGR cooler having a plurality of tubes through which exhaust gas flows inside, and a casing that houses the tubes, A waste heat recovery device for a vehicle that performs heat exchange between the exhaust gas and the cooling water through the tube by flowing the cooling water into the casing. The waste heat recovery device for the vehicle is a gas inlet portion for introducing the exhaust gas into the tube, a gas outlet portion for discharging the exhaust gas from the tube, a water inlet portion for introducing the cooling water into the casing, and a water outlet portion for discharging the cooling water from the casing. The water outlet portion has a main body portion that forms a water outlet passage through which the cooling water passes, and a blocking portion that extends in a direction away from the water inlet portion from the main body portion closer to the water inlet portion than the water outlet passage. The blocking portion extends so as to face the water outlet passage. The tip of the blocking portion has a central portion corresponding to the water outlet passage extending to the side opposite to the water inlet portion from its end portion. A waste heat recovery device for a vehicle.

Images