JP2007309549A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve heat exchanging efficiency when carbon dioxide as a heat exchanging medium is circulated in a plurality of paths. <P>SOLUTION: A radiator is composed of a tube and a header tank. A partitioning plate is disposed in the header tank, and the tube is divided into first-third paths P1-P3. A flow channel cross-sectional area of the first path P1 is wider than flow channel cross-sectional areas of the second path P2 and the third path P3. The radiator 1 is loaded in an engine room E in a state that the first path P1 is corresponded to an opening portion S of a vehicle front part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat exchanger used in, for example, an air conditioner and the like, and particularly belongs to a technical field of a structure that improves heat exchange efficiency between a heat exchange medium flowing inside and air flowing outside.

  Conventionally, for example, as disclosed in Patent Document 1, a refrigeration apparatus constituting a vehicle air conditioner is provided with a heat exchanger used as a condenser for condensing a heat exchange medium in a gaseous state. . This heat exchanger includes a core formed by alternately arranging flat tubes and fins, and header tanks respectively disposed at both ends of the core so as to communicate with the tubes. The internal spaces of these header tanks are partitioned in the direction in which the tubes are arranged side by side. Three tubes as flow path constituting parts constituting the flow path of the heat exchange medium are formed by tubes communicating with the spaces of the header tank in a state where the paths communicate with each other in the flow direction of the heat exchange medium. The number of tubes constituting the upstream path located in the most upstream flow direction of the heat exchange medium is the largest, the flow path cross-sectional area is secured widely, and the number of tubes constituting the downstream path located in the most downstream is the smallest. The road cross-sectional area is narrowed. As a result, the cross-sectional area of the flow path can be made narrower toward the downstream side in order to cope with the phase change of the heat exchange medium in the gaseous state during the condensation process, resulting in a decrease in volume. Improvement is achieved.

On the other hand, for example, as disclosed in Patent Document 2, a heat exchanger used for a refrigeration apparatus using carbon dioxide having a low environmental impact as a heat exchange medium is known. When carbon dioxide is used as the heat exchange medium, the critical temperature of carbon dioxide is as low as 31 ° C., so even if the high-temperature and high-pressure carbon dioxide is cooled by a heat exchanger, the phase does not change in a supercritical state. The volume of is not reduced much compared to the phase change refrigerant.
JP-A-63-161393 JP 2001-221580 A

  By the way, when the volume of the heat exchange medium does not decrease so much in the heat exchanger as in Patent Document 2, the flow path of the path increases toward the downstream side in the flow direction of the heat exchange medium as in the heat exchanger of Patent Document 1. If the cross-sectional area is narrowed, the flow path cross-sectional area of each path does not correspond to the volume of the heat exchange medium, and high heat exchange efficiency may not be obtained.

  The present invention has been made in view of such points, and an object of the present invention is to provide a flow path configuration in consideration of the flow velocity of air flowing outside when the heat exchange medium does not change phase in the heat exchanger. By forming the portion, the heat exchange efficiency is improved.

  In order to achieve the above object, according to the first aspect of the present invention, the first flow path constituting part constituting the flow path of the heat exchange medium and the second flow constituting the flow path communicating with the first flow path constituting part. A heat exchange medium that is higher in temperature than the air flowing outside the two flow path components, and configured to exchange heat with air without phase change in the flow channel components. In the exchanger, the first flow path component is upstream of the second flow path component in the flow direction of the heat exchange medium and from a region where the second flow path component is disposed. Also, it is configured to be arranged in a region where the air flow rate is high.

  According to this configuration, since the heat exchange medium flows through the first flow path component and is cooled, then the heat exchange medium flows through the second flow path component and is further cooled. The temperature is higher than that of the heat exchange medium flowing through the second flow path component, and the temperature difference with air is relatively large. Since the flow velocity of air flowing toward the first flow path component where the heat exchange medium having a larger temperature difference from the air is larger than that of the second flow path component is high, the amount of heat exchange per unit time should be increased. Is possible.

  In the invention of claim 2, in the invention of claim 1, in the invention of claim 1, the first flow path constituting portion is connected to the inflow portion of the heat exchange medium.

  According to this configuration, the heat exchange medium that has flowed into the first flow path component from the inflow portion has the highest temperature among the heat exchange media flowing in the heat exchanger, and flows toward the first flow path component. Since the flow rate of air is high, the amount of heat exchange per unit time can be further increased.

  The invention according to claim 3 includes a first flow path component that forms a flow path of the heat exchange medium, and a second flow path component that forms a flow path that communicates with the first flow path component, A heat exchanger configured such that a heat exchange medium at a higher temperature than air flowing outside both flow path components exchanges heat with air in the flow path components without causing a phase change. The one flow path component has a flow channel cross-sectional area larger than the flow channel cross-sectional area of the second flow path component, and the air flow velocity is faster than the region where the second flow path component is disposed. The configuration is arranged in the area.

  According to this configuration, since the volume of the heat exchange medium that does not change phase does not change so much in the heat exchanger, the flow rate of the heat exchange medium that flows through the first flow path component having a large flow path cross-sectional area is the second flow path. It becomes slower than the flow rate of the heat exchange medium flowing through the component. Since the flow rate of the air flowing toward the first flow path component, which is slower than the second flow path component, is higher than the flow rate of the heat exchange medium, the heat exchange medium is sufficiently in the air while flowing through the first flow path component. Heat exchange.

  According to a fourth aspect of the present invention, the apparatus includes: a first flow path component that forms a flow path of the heat exchange medium; and a second flow path component that forms a flow path that communicates with the first flow path component. An opening provided in the front part of the vehicle is configured such that a heat exchange medium in a higher temperature state than the air flowing outside the two flow path components exchanges heat with the air without phase change in the flow channel components. A heat exchanger mounted on the rear side of the unit, wherein the first flow path component is upstream of the second flow path component in the flow direction of the heat exchange medium and corresponds to the opening. It is set as the structure arrange | positioned.

  According to this configuration, since the first flow path component is disposed so as to correspond to the opening of the vehicle, there is a heat exchange medium in which the temperature difference from the air is larger than that of the second flow path component. It becomes possible to increase the flow velocity of the air flowing toward the one flow path component. Thereby, it becomes possible to increase the amount of heat exchange per unit time.

  The invention according to claim 5 includes a first flow path component that forms a flow path of the heat exchange medium, and a second flow path component that forms a flow path that communicates with the first flow path component, An opening provided in the front part of the vehicle is configured such that a heat exchange medium in a higher temperature state than the air flowing outside the two flow path components exchanges heat with the air without phase change in the flow channel components. A heat exchanger mounted on a rear side of the first flow path, wherein the first flow path component has a flow path cross-sectional area wider than that of the second flow path structure, and the opening It is set as the structure arrange | positioned corresponding to.

  According to this configuration, it is possible to increase the flow rate of the air flowing toward the first flow path component that is slower than the second flow path component. As a result, the heat exchange medium sufficiently exchanges heat with air while flowing through the first flow path component.

  According to a sixth aspect of the invention, in the third or fifth aspect of the invention, the first flow path component is disposed upstream of the second flow path component in the flow direction of the heat exchange medium.

  According to this configuration, similarly to the first aspect of the invention, it is possible to increase the amount of heat exchange per unit time.

  According to a seventh aspect of the present invention, in any one of the first to sixth aspects of the present invention, a plurality of tubes arranged in parallel in a direction crossing the air flow direction, and the end portions respectively disposed at both ends of the tubes. The header tank communicates with the internal space of the header tank, and the internal space of the header tank is partitioned into one side and the other side in the juxtaposed direction of the tubes.

  According to this structure, it becomes possible to form a 1st flow path structure part and a 2nd flow path structure part with a tube. The flow path cross-sectional areas of these flow path components are changed by changing the partition position of the internal space of the header tank.

  According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the heat exchange medium is carbon dioxide.

  According to the first aspect of the present invention, since the first flow path component in which the heat exchange medium having a large temperature difference from the air flows is arranged in a region where the flow velocity of air is high, the amount of heat exchange per unit time can be increased, Heat exchange efficiency can be improved.

  According to the third aspect of the present invention, the first flow path component through which the heat exchange medium having a low flow velocity flows is disposed in the region where the air flow velocity is high. Therefore, the air is exchanged while the heat exchange medium flows through the first flow channel component. The heat exchange efficiency can be improved by sufficiently exchanging heat.

  According to invention of Claim 4, the 1st flow-path structure part through which the heat exchange medium with a large temperature difference with air flows can be arrange | positioned in the area | region where the flow velocity of the air in a vehicle is quick, and heat exchange efficiency can be improved.

  According to invention of Claim 5, the 1st flow-path structure part through which the heat exchange medium with a slow flow velocity flows can be arrange | positioned in the area | region where the flow velocity of air is quick, and heat exchange efficiency can be improved.

  According to the invention of claim 6, the heat exchange efficiency can be further improved.

  According to the seventh aspect of the present invention, it is possible to easily change the flow path cross-sectional areas of the first and second flow path components only by changing the partition position of the internal space of the header tank.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

  FIG. 1 shows a heat exchanger according to an embodiment of the present invention. In the description of this embodiment, a case will be described in which the heat exchanger is the radiator 1 that is one element of the refrigeration apparatus that constitutes the automotive air conditioner. As shown in FIGS. 2 and 4, the radiator 1 is mounted in an engine room E provided at the front portion of the automobile A. A support member (not shown) is provided at the front end of the engine room E, and the radiator 1 is supported by the support member.

  First, the structure of the automobile A will be described. At the front of the automobile A, a hood hood B that covers the engine room E from above is provided. A front bumper C is provided below the front edge of the hood hood B. Between the front bumper C and the front edge of the hood hood B, an opening S for taking cooling air into the engine room E is formed. The front bumper C is provided with a grill D at a portion corresponding to the opening S. A cooling fan (not shown) is disposed in the engine room E.

  Next, the refrigeration apparatus will be described. Although not shown, this refrigeration apparatus includes a compressor, the radiator 1, the expansion valve, and the evaporator, which are connected in order to a closed circuit by piping. Among these, the compressor and the radiator 1 are disposed in the engine room E, and the expansion valve and the evaporator are disposed in the vehicle interior. The heat exchange medium charged in the refrigeration apparatus is carbon dioxide. The carbon dioxide sucked into the compressor is compressed into a high temperature and high pressure state, and the high temperature and high pressure carbon dioxide flows into the radiator 1 and is cooled by exchanging heat with external air. The carbon dioxide flowing out of the radiator 1 passes through the expansion valve, is depressurized and flows into the evaporator, exchanges heat with external air, cools the air, and is sucked into the compressor.

  As shown in FIG. 1, the radiator 1 includes a core 4 in which tubes 2 through which carbon dioxide flows and heat transfer fins 3 are alternately arranged in the vertical direction, and the longitudinal direction of the tube 2 of the core 4. A first header tank 5 and a second header tank 6 provided at both ends so as to communicate with the end of the tube 2, and an upper end plate 7 and a lower side provided at the upper and lower ends of the core 4. And an end plate 8. In the description of this embodiment, the left side in FIG. 1 is referred to as the left side of the radiator 1, and the right side in FIG. 1 is referred to as the right side of the radiator 1.

  The tube 2 is a flat tube having a long cross-sectional shape in the flow direction of external air and extending in the left-right direction, and is made of an aluminum alloy. The fin 3 is a corrugated fin having a wave shape when viewed along the flow direction of the external air, and is made of a thin plate material of aluminum alloy. The outer surface of the tube 2 or the surface of the fin 3 is coated with a brazing material, and the tube 2 and the fin 3 are brazed and integrated with the brazing material.

  The said 1st header tank 5 is arrange | positioned at the left side of the heat radiator 1, and is formed in the cylindrical shape extended long in an up-down direction. The peripheral wall 13 of the first header tank 5 is formed by bending an aluminum alloy plate. A brazing material is applied to the plate material constituting the peripheral wall portion 13.

  The upper end portion and the lower end portion of the peripheral wall portion 13 of the first header tank 5 protrude above and below the upper end portion and the lower end portion of the core 4, respectively. An upper end opening and a lower end opening (both not shown) of the peripheral wall portion 13 are closed by an upper cap 14 and a lower cap 15. These caps 14 and 15 are brazed to the peripheral wall portion 13. Similarly, the second header tank 6 includes a peripheral wall portion 13 and caps 14 and 15.

  A number of tube insertion holes (not shown) into which the end of the tube 2 is inserted are formed in the peripheral wall portion 13 at intervals in the vertical direction. These tube insertion holes are formed in a slit shape long in the circumferential direction of the peripheral wall portion 13. The end of the tube 2 is brazed to the peripheral edge of the tube insertion hole while being inserted into the tube insertion hole and communicating with the internal space.

  The first header tank 5 is provided with a first partition plate 12 as a partition member that partitions the internal space of the first header tank 5 in the vertical direction that is the direction in which the tubes 2 are arranged side by side. The first partition plate 12 is made of an aluminum alloy plate, and is inserted into a slit-like insertion hole (not shown) formed in the peripheral wall portion 13 and brazed to the peripheral wall portion 13. ing. The vertical position of the first partition plate 12 can be easily changed by changing the position of the insertion hole formed in the peripheral wall portion 13.

  An introduction pipe 16 that communicates with the space above the first partition plate 12 is provided at the top of the first header tank 5. Carbon dioxide discharged from the compressor is introduced into the space above the first partition plate 12 of the first header tank 5 through the introduction pipe 16. The introduction pipe 16 constitutes the inflow portion of the present invention.

  Similarly to the first header tank 5, the second header tank 6 is also provided with a second partition plate 18 that partitions the internal space of the second header tank 6 in the direction in which the tubes 2 are juxtaposed. The partition plate 18 is disposed below the first partition plate 12. A discharge pipe 17 that communicates with a space below the second partition plate 18 is provided at the lower portion of the second header tank 6. The carbon dioxide in the radiator 1 is discharged to the outside through the discharge pipe 17.

  The tube 2 positioned above the first partition plate 12 constitutes a first path P1 connected to the introduction pipe 16. The second path P2 is configured by the tube 2 positioned between the first partition plate 12 and the second partition plate 18, and the third path P3 is configured by the tube 2 positioned below the second partition plate 18. Is configured. These first to third paths P1 to P3 are connected and communicated in order from the upstream side to the downstream side in the flow direction of carbon dioxide by the internal space of the header tanks 5 and 6. The first to third paths P1 to P3 are flow path components that constitute a flow path for carbon dioxide.

  The flow path cross-sectional areas of the first to third paths P1 to P3 are determined by the number of tubes 2 constituting each of the paths P1 to P3. The flow path cross-sectional areas of the paths P1 to P3 can be changed depending on the positions of the first partition plate 12 and the second partition plate 18, and in this embodiment, the flow path cross-sectional area of the first path P1 is the second path P2. In addition, the flow path cross-sectional area of the third path P3 is set to be wider, and the flow path cross-sectional area of the second path P2 is set to be wider than the flow path cross-sectional area of the third path P3.

  The upper end plate 7 is formed by forming an aluminum alloy plate so as to have a substantially U-shaped cross section that opens upward, and extends over both ends of the core 4 in the left-right direction. The left and right ends of the upper end plate 7 are provided with contact portions 7 a that come into contact with the outer surfaces of the peripheral wall portions 13 of the first header tank 5 and the second header tank 6. These contact portions 7 a are brazed to the outer surface of the peripheral wall portion 13. The lower end plate 8 is configured in the same manner as the upper end plate 7, and the contact portion 8 a is brazed to the outer surface of the peripheral wall portion 13 of the first header tank 5 and the second header tank 6.

  As indicated by arrows in FIG. 3, the carbon dioxide flowing into the first header tank 5 from the introduction pipe 16 of the radiator 1 flows into the first path P <b> 1 to the second header tank 6 side. Flows into the space above the second partition plate 18 of the second header tank 6. The carbon dioxide flowing into the second header tank 6 flows into the second path P2, flows to the first header tank 5, and flows into the space below the first partition plate 12 of the first header tank 5. To do. The carbon dioxide that has flowed into the space below the first header tank 5 flows into the third path P3 and flows through the tube 2 toward the second header tank 6, and the second partition plate of the second header tank 6. It flows into the space below 18 and is discharged from the discharge pipe 17 to the outside.

  As shown in FIG. 4A, the radiator 1 configured as described above is supported by a support member in a state where the first path P1 is disposed so as to correspond to the opening S of the vehicle. By making the first path P1 correspond to the opening S in this way, the opening S and the first path P1 overlap when the vehicle is viewed from the front.

  When the vehicle is running or when the cooling fan is rotating while the vehicle is stopped, air is taken into the engine room E from the opening S. At this time, the wind velocity distribution immediately after the opening S in the engine room E is substantially as shown in FIG. 4B, and the flow velocity of the air flowing through the region corresponding to the opening S is the fastest. The first path P1 of the radiator 1 is located in a region where the air flow is fast. That is, the first path P1 is the first flow path component of the present invention, and the second path P2 is the second flow path component of the present invention.

  On the other hand, since the carbon dioxide discharged from the compressor flows through the first path P1 of the radiator 1 and is cooled and then flows through the second path P2 and is further cooled, the temperature of the carbon dioxide flowing through the first path P1. Is higher than the temperature of carbon dioxide flowing through the second path P2, and has a large temperature difference from air. Since the flow velocity of the air flowing toward the first path P1 in which carbon dioxide having a larger temperature difference from the air is larger than that in the second path P2, the heat exchange amount per unit time can be increased.

  In addition, since the volume of carbon dioxide that does not change phase does not change much in the radiator 1, the flow rate of carbon dioxide flowing through the first path P1 having a large flow path cross-sectional area is higher than the flow rate of carbon dioxide flowing through the second path P2. Become slow. Since the flow rate of the air flowing toward the first path P1, which is slower than the second path P2, is high, the carbon dioxide sufficiently exchanges heat with the air while flowing through the first path P1.

  As described above, according to the radiator 1 according to this embodiment, the first path P1 in which carbon dioxide flows having a large temperature difference from the air as compared with the second path P2 and the third path P3 flows through the first path P1. Since it arrange | positions in the area | region where a flow rate is quick, and also the flow rate of the carbon dioxide which flows through the 1st path | pass P1 is made slower than other path | pass P2, P3, heat exchange efficiency can fully be improved.

  Further, since the radiator 1 is composed of a large number of tubes 2 and header tanks 5 and 6, the positions of the paths P1 to P3 and the flow path cross-sectional areas of the paths P1 to P3 can be arbitrarily and easily changed.

  In the above embodiment, the first path P1 having a flow path cross-sectional area wider than the flow path cross-sectional areas of the second path P2 and the third path P3 is arranged in a region where the air flow velocity is fast. For example, as in Modification 1 shown in FIG. 5, the flow path cross-sectional area of the second path P2 is made wider than the flow path cross-sectional areas of the first path P1 and the third path P3, and as shown in FIG. The second path P2 may correspond to the opening S.

  Further, for example, when the vehicle is provided with the upper opening S1 and the lower opening S2 with an interval as in the second modification shown in FIGS. 7 and 8, the first path P1 and the second The flow path cross-sectional area of the 3-pass P3 is made larger than the flow-path cross-sectional area of the second pass P2, and the first pass P1 and the third pass P3 correspond to the upper opening S1 and the lower opening S2, respectively. It may be arranged. In this case, the flow path cross-sectional area of the first path P1 and the flow path cross-sectional area of the third path P3 may be set to be approximately the same or different.

  Further, the flow path cross-sectional area of the first path P1 may be narrower than that of the second path P2 and the third path P3 and may be arranged in a region where the air flow velocity is fast, or the second path P2 and the third path. You may make it arrange | position in the area | region where the flow-path cross-sectional area of P3 is enlarged, and the flow velocity of air is quick.

  Further, the introduction pipe 16 may be provided in the lower part of the first header tank 5, and the discharge pipe 17 may be provided in the upper part of the second header tank 6. In this case, the third path P3 is the path on the most upstream side in the flow direction of carbon dioxide. Further, by changing the number of the first partition plates 12 of the first header tank 5 and the number of the second partition plates 18 of the second header tank 6, the number of passes can be made two, four or more.

  The present invention can also be applied to a radiator for heating in a passenger compartment.

  The present invention can also be applied to a radiator of a refrigeration apparatus used other than an air conditioner.

  Moreover, in this embodiment, although the case where the heat exchanger is a radiator for a supercritical cycle using carbon dioxide as a heat exchange medium is described, as the heat exchange medium, in addition to carbon dioxide, for example, Any material may be used as long as it is used in a supercritical region such as ethylene, ethane, or nitric oxide.

  As described above, the heat exchanger according to the present invention is suitable as a radiator of a refrigeration apparatus used for a vehicle air conditioner, for example.

It is a front view of the heat radiator which concerns on embodiment of this invention. It is the schematic which looked at the state which mounted the heat radiator in the engine room of the vehicle from the front side. It is the schematic of a heat radiator. (A) is the schematic which looked at the vehicle front part in which the heat radiator was mounted from the side, (b) is the side view of the heat sink corresponding to the wind speed distribution just behind an opening part, and it. FIG. 6 is a view corresponding to FIG. 3 according to Modification 1 of the embodiment. FIG. 5 is a diagram corresponding to FIG. 4 according to Modification 1 of the embodiment. FIG. 6 is a view corresponding to FIG. 3 according to a second modification of the embodiment. FIG. 5 is a diagram corresponding to FIG. 4 according to a second modification of the embodiment.

Explanation of symbols

1 radiator (heat exchanger)
2 Tube 3 Fin 5 1st header tank 6 2nd header tank 12 1st partition plate 16 Introducing pipe (inflow part)
17 Discharge pipe 18 2nd partition plate A Car E Engine rooms P1 to P3 1st to 3rd path (flow path component)
S opening S1 upper opening S2 lower opening

Claims (8)

A first flow path component that forms a flow path of the heat exchange medium, and a second flow path component that forms a flow path that communicates with the first flow path component; A heat exchanger configured to exchange heat with air without causing a phase change in the flow path component, the heat exchange medium having a higher temperature than the air flowing through the flow path,
The first flow path component is upstream of the second flow path component in the flow direction of the heat exchange medium and has a higher air flow rate than the region where the second flow path component is disposed. A heat exchanger which is arranged in a region. The heat exchanger according to claim 1,
The first flow path component is connected to an inflow portion of a heat exchange medium. A first flow path component that forms a flow path of the heat exchange medium, and a second flow path component that forms a flow path that communicates with the first flow path component; A heat exchanger configured to exchange heat with air without causing a phase change in the flow path component, the heat exchange medium having a higher temperature than the air flowing through the flow path,
The first flow path component has a flow path cross-sectional area larger than the flow path cross-sectional area of the second flow path component, and the air flow velocity is higher than the region where the second flow path component is disposed. The heat exchanger is arranged in a fast region. A first flow path component that forms a flow path of the heat exchange medium, and a second flow path component that forms a flow path that communicates with the first flow path component; The heat exchange medium at a higher temperature than the air flowing through the air is configured to exchange heat with the air without phase change in the flow path component, and is mounted on the rear side of the opening provided in the front of the vehicle. A heat exchanger,
The heat exchanger according to claim 1, wherein the first flow path component is disposed on the upstream side of the second flow path component in the flow direction of the heat exchange medium and corresponding to the opening. A first flow path component that forms a flow path of the heat exchange medium, and a second flow path component that forms a flow path that communicates with the first flow path component; The heat exchange medium at a higher temperature than the air flowing through the air is configured to exchange heat with the air without phase change in the flow path component, and is mounted on the rear side of the opening provided in the front of the vehicle. A heat exchanger,
The first flow path component has a flow channel cross-sectional area larger than that of the second flow path component, and is disposed so as to correspond to the opening. vessel. The heat exchanger according to claim 3 or 5,
The first flow path component is disposed on the upstream side of the second flow path component in the flow direction of the heat exchange medium. The heat exchanger according to any one of claims 1 to 6,
A plurality of tubes arranged side by side in a direction crossing the air flow direction, and header tanks respectively disposed at both ends of the tubes and communicating with the ends;
An internal space of the header tank is partitioned into one side and the other side in the juxtaposed direction of the tubes. The heat exchanger according to any one of claims 1 to 7,
A heat exchanger characterized in that the heat exchange medium is carbon dioxide.

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