JP2006153437A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger whose heat exchanging performance is prevented from deteriorating while requiring a relatively smaller installation space. <P>SOLUTION: The heat exchanger 1 comprises a plurality of heat exchanging parts 2 arranged in parallel, and a pair of connectors 3 which are spaced from each other and to which all heat exchanging parts 2 are connected at both ends. Each heat exchanging part 2 has a first fluid passage 6 and a second fluid passage 7 formed around the first fluid passage 6. Each connector 3 has a first flow path 13 for communicating the first fluid passage 6 of the heat exchanging part 2 with the outside and a second flow path 16 independent from the first flow path 13 for communicating the second fluid passage 7 of the heat exchanging part 2 with the outside. The heat exchanging part 2 consists of an outer tube 4 and an inner tube 5 arranged in the outer tube 4 at a space. The first fluid passage 6 exists in the inner tube 4, and the second fluid passage 7 exists in a gap between the outer tube 4 and the inner tube 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a heat exchanger, and more specifically, for example, an intermediate for exchanging heat between a refrigerant coming out of a compressor, a gas cooler, an evaporator, a gas-liquid separator and a gas cooler and a refrigerant coming out of the evaporator and passed through the gas-liquid separator. The present invention relates to a heat exchanger that is suitably used as an intermediate heat exchanger in a supercritical refrigeration cycle that includes a heat exchanger and uses a supercritical refrigerant such as CO ₂ .

  In this specification and claims, the term “aluminum” includes aluminum alloys in addition to pure aluminum. Further, in this specification and claims, the “supercritical refrigeration cycle” means a refrigeration cycle in which the refrigerant is in a supercritical state exceeding the critical pressure on the high-pressure side. The term “refrigerant” means a refrigerant used in a supercritical refrigeration cycle.

  2. Description of the Related Art Conventionally, car air conditioners mounted on automobiles are widely used that are composed of a compressor, a condenser, an evaporator, a gas-liquid separator, and a decompressor, and a refrigeration cycle that uses a chlorofluorocarbon refrigerant.

By the way, in recent years, it has been considered to mount a supercritical refrigeration cycle using a supercritical refrigerant such as CO _{2 in} a car as a car air conditioner.

  The supercritical refrigeration cycle consists of a compressor, a gas cooler, an evaporator, an accumulator as a gas-liquid separator, an expansion valve as a decompressor, and a low-temperature and low-pressure An intermediate heat exchanger that exchanges heat with the refrigerant is provided.

  By the way, the intermediate heat exchanger in the supercritical refrigeration cycle is a heat exchanger that was not found in the conventional refrigeration cycle using the chlorofluorocarbon refrigerant, and can efficiently store the intermediate heat exchanger in the engine room of the automobile. At present, it is considered to be disposed in a portion between the gas cooler and the evaporator in the engine room.

  As a heat exchanger used for the intermediate heat exchanger of the supercritical refrigeration cycle described above, one heat exchange tube having one inner fluid hole and a plurality of outer fluid holes formed at intervals around the inner fluid hole, Two inner fluid hole connectors fixed to both ends of the heat exchange pipe and having a flow path leading to the inner fluid hole, and fixed to the inner side in the length direction of the heat exchange pipe than the inner fluid hole connector and outside 2. Description of the Related Art There are known two outer fluid hole connectors having flow paths that communicate with fluid holes (see Patent Document 1).

  By the way, in the intermediate heat exchanger described in Patent Document 1, in order to obtain a desired heat exchange performance between the refrigerant flowing in the inner fluid hole and the refrigerant flowing in the outer fluid passage hole, the fluid flowing in both fluid holes It is necessary to increase the heat transfer area. However, in this case, it is necessary to increase the length of the heat exchange pipe, and there is a problem that the installation space in the length direction of the heat exchange pipe in the intermediate heat exchanger becomes relatively large.

Therefore, as an intermediate heat exchanger that solves such a problem, a pair of header tanks arranged at a distance from each other, a parallel arrangement between both header tanks, and both ends connected to the header tank A plurality of flat heat exchange pipes, and each header tank is a double pipe structure comprising a first header pipe and a second header pipe disposed in the first header pipe. The first fluid passage and the second fluid passage are formed, and both ends of the heat exchange pipe are connected so that the first fluid passage communicates with the first header pipe and the second fluid passage communicates with the second header pipe. The thing connected to both header tanks is also known (refer patent document 2). In the intermediate heat exchanger described in Patent Document 2, it is possible to increase the heat transfer area between the fluids flowing in both fluid passages, and the length of the flat heat exchange pipe is set to the intermediate heat exchanger described in Patent Document 1. Can be shortened compared to However, in the intermediate heat exchanger described in Patent Document 2, since the plurality of first fluid passages and second fluid passages are formed in the flat heat exchange pipe, the cross-sectional area of both fluid passages is reduced, There is a possibility that the pressure loss increases and the heat exchange performance decreases.
JP 2000-2492 A JP2003-121086

  An object of the present invention is to provide a heat exchanger that can solve the above-described problems, can reduce the installation space, and can prevent deterioration in heat exchange performance.

  In order to achieve the above object, the present invention comprises the following aspects.

  1) A plurality of heat exchanging portions arranged in parallel and a pair of connectors arranged at intervals and connected to both ends of all the heat exchanging portions. A first fluid passage and a second fluid passage formed around the first fluid passage, and each connector communicates the first fluid passages of all the heat exchanging parts to the outside, and The heat exchanger which has the 2nd flow path which makes the 2nd fluid channel | path of all the heat exchange parts independent outside with respect to 1 flow path outside.

  2) The heat exchanger according to 1) above, wherein heat transfer fins are provided in the second fluid passage of the heat exchange section.

  3) The heat exchange part is formed by an outer tube and an inner tube arranged in the outer tube at an interval. The inner tube serves as a first fluid passage, and between the outer tube and the inner tube. The heat exchanger according to 1) or 2) above, wherein the gap serves as the second fluid passage.

  4) The heat exchanger according to 3) above, wherein heat transfer fins are integrally formed on the outer peripheral surface of the inner pipe so as to be spaced apart in the circumferential direction and extend in the length direction of the inner pipe.

  5) The heat exchanger according to 3) or 4) above, wherein the outer tube, the inner tube and the connector are made of aluminum.

  6) The heat exchanger according to 5) above, wherein the outer tube and the inner tube are made of extruded aluminum.

  7) The heat exchanger according to 1) above, wherein each connector is formed by a first connector member having a first flow path and a second connector member having a second flow path.

  8) The heat exchange part is formed by an outer tube and an inner tube arranged in the outer tube with a space therebetween, and the inner tube serves as a first fluid passage, and between the outer tube and the inner tube. The gap serves as a second fluid passage, the first connector member is disposed on the outer side in the length direction of the heat exchanging portion with respect to the second connector member, and both end portions of the inner tube protrude outward from both ends of the outer tube. The heat exchanger according to 7), wherein the outer projecting portion of the inner tube is connected to the first connector member in a state of passing through the second connector member, and the outer tube is connected to the second connector member.

  9) The heat exchanger according to 8) above, wherein heat transfer fins are provided in the second fluid passage.

  10) The heat exchanger according to 9) above, wherein the heat transfer fins are integrally formed on the outer peripheral surface of the inner tube so as to be spaced apart in the circumferential direction and extend in the length direction of the inner tube.

  11) The heat exchanger according to any one of 8) to 10) above, wherein the first and second connector members, the outer tube, and the inner tube are made of aluminum.

  12) The heat exchanger according to 11) above, wherein the outer tube and the inner tube are made of extruded aluminum.

  13) The compressor, the gas cooler, the evaporator, the gas-liquid separator, and the intermediate heat exchanger that exchanges heat between the refrigerant coming out of the gas cooler and the refrigerant coming out of the evaporator and passing through the gas-liquid separator, and A supercritical refrigeration cycle using a critical refrigerant, wherein the intermediate heat exchanger is a heat exchanger described in any one of 1) to 12) above.

  14) The high-pressure refrigerant coming out of the gas cooler flows in the first fluid passage of the intermediate heat exchanger, and the low-pressure refrigerant coming out of the evaporator and passes through the gas-liquid separator also flows in the second fluid passage. The supercritical refrigeration cycle as described in 13) above.

  15) The supercritical refrigeration cycle according to 13) or 14) above, wherein the supercritical refrigerant is carbon dioxide.

  16) A vehicle on which the supercritical refrigeration cycle according to any one of the above 13) to 15) is mounted as a car air conditioner.

  According to the heat exchanger of 1) above, it is assumed that the total heat transfer area between the fluids flowing in the first and second fluid passages of the heat exchange part is set to a size necessary for obtaining a desired heat exchange performance. However, the dimension in the length direction of the heat exchange part can be shortened compared to the heat exchanger described in Patent Document 1. Therefore, the installation space in the length direction of the heat exchanging portion of this heat exchanger can be reduced as compared with the case of the heat exchanger described in Patent Document 1. Moreover, since the cross-sectional area of the first and second fluid passages can be made larger than the cross-sectional area of the first and second fluid passages of the heat exchanger described in Patent Document 2, pressure loss is reduced. As a result, a decrease in heat exchange performance can be prevented.

  According to the heat exchanger of 2) above, the heat exchanger tube performance of each heat exchange part is improved by the action of the heat transfer fins, so the length of the heat exchange part is shortened or the number of heat exchange parts is reduced. As a result, the installation space for the heat exchanger can be reduced.

  According to the heat exchanger of 3) above, the heat exchange part can be formed relatively easily. In addition, since the cross-sectional area of the first and second fluid passages can be easily made larger than the cross-sectional area of the first and second fluid passages of the heat exchanger described in Patent Document 2, the pressure loss As a result, it is possible to prevent a decrease in heat exchange performance.

  According to the heat exchanger of 4) above, the heat transfer fins are formed integrally with the inner tube, so the number of parts is reduced and the heat transfer efficiency between the fluids flowing in both fluid passages is improved.

  According to the heat exchanger of 5) above, the heat transfer efficiency between the fluids flowing in both fluid passages is improved.

  According to the heat exchanger of 6), the outer tube and the inner tube can be manufactured relatively easily. In particular, when the heat transfer fin is formed integrally with the inner pipe as in the above 4), the inner pipe can be easily manufactured.

  According to the heat exchanger of 8) above, the heat exchange part can be formed relatively easily. Further, the inner pipe and the first connector member can be connected so that the first fluid passage in the inner pipe communicates reliably with the first flow path of the first connector member, and the second fluid passage between the inner and outer pipes. It is possible to connect the outer tube and the second connector member so as to reliably communicate with the second flow path of the second connector member. In addition, since the cross-sectional area of the first and second fluid passages can be easily made larger than the cross-sectional area of the first and second fluid passages of the heat exchanger described in Patent Document 2, the pressure loss As a result, it is possible to prevent a decrease in heat exchange performance.

  According to the heat exchanger of 9) above, the heat exchange tube performance of each heat exchange part is improved by the action of the heat transfer fins, so the length of the heat exchange part is shortened or the number of heat exchange parts is reduced. As a result, the installation space for the heat exchanger can be reduced.

  According to the heat exchanger of 10) above, since the heat transfer fins are formed integrally with the inner tube, the number of parts is reduced and the heat transfer efficiency between the fluids flowing in both fluid passages is improved.

  According to the heat exchanger of the above 11), the heat transfer efficiency between fluids flowing in both fluid passages is improved.

  According to the heat exchanger of 12) above, the outer tube and the inner tube can be manufactured relatively easily. In particular, when the heat transfer fin is formed integrally with the inner pipe as in the above 10), the inner pipe can be easily manufactured.

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

  In the following description, the upper and lower sides and the left and right sides in FIGS.

  FIG. 1 shows the overall configuration of a heat exchanger according to the present invention, and FIGS. 2 and 3 show the configuration of the main part thereof. FIG. 4 shows a supercritical refrigeration cycle using the heat exchanger according to the present invention as an intermediate heat exchanger.

  As shown in FIG. 1, the heat exchanger (1) is arranged in parallel with a plurality of, in this case, two heat exchanging units (2) arranged in parallel in the vertical direction. And a pair of connectors (3) to which both ends of all the heat exchanging parts (2) are connected.

  Each heat exchange section (2) is formed by an outer tube (4) extending in the left-right direction and an inner tube (5) extending in the left-right direction inserted concentrically in the outer tube (4). The inner pipe (5) is the first fluid passage (6) and the gap between the outer pipe (4) and the inner pipe (5) is the second fluid passage (7). .

  As shown in FIGS. 2 and 3, the outer tube (4) is made of a metal, here an aluminum extruded profile. The inner pipe (5) is made of a metal, here, an aluminum extruded shape, and on its outer peripheral surface, a plurality of heat transfer fins (8) are spaced in the circumferential direction, and the length direction of the inner pipe (5) It is integrally formed so that it may extend. There is a slight gap between the tip of the heat transfer fin (8) and the inner peripheral surface of the outer tube (4). Both end portions of the inner tube (5) protrude outward from the outer tube (4), and the heat transfer fin (8) is cut out over the entire outer protrusion (5a) having a predetermined length. A plurality of inner fins (9) extending over the entire length are integrally formed on the inner peripheral surface of the inner pipe (5) at intervals in the circumferential direction.

  Each connector (3) is composed of a metal, here an aluminum block, and the first connector member (11) arranged in the left-right direction, that is, outside the length direction of the heat exchange part (2), the metal, Is formed of an aluminum block and the second connector member (12) disposed on the inner side in the left-right direction. The left and right connectors (3) are symmetrical, and the left connector (3) will be described in detail below.

  The first connector member (11) is formed with a first flow path (13) that extends from the upper end surface to the vicinity of the lower end and communicates with the first fluid passage (6) of the heat exchange section (2). Also, the first connector member (11) has the same number of laterally penetrating communication as the heat exchange section (2) having one end opened on the right side and the other end opened on the inner peripheral surface of the first flow path (13). Holes (14) are formed at intervals in the vertical direction. A large diameter portion (15) for fitting an inner pipe is formed at the right end portion of each communication hole (14).

  The second connector member (12) is formed with a second flow path (16) that extends from the upper end surface to the vicinity of the lower end and communicates with the second fluid passage (7) of the heat exchange section (2). In addition, the second connector member (12) has a bottom-like communication in the lateral direction with the same number as the heat exchanging portion (2) whose one end is open on the right side and the other end is on the left side of the second flow path (16). Holes (17) are formed at intervals in the vertical direction. A large-diameter portion (18) for fitting an outer tube is formed at the right end of each communication hole (17). Note that the height positions of the centers of the communication holes (14) and (17) of both the connector members (11) and (12) are the same. Further, the second connector member (12) is formed with an inner tube insertion through hole (19) having one end opened on the bottom surface of each communication hole (17) and the other end opened on the left side surface.

  The outward protrusion (5a) of the inner pipe (5) of the heat exchange part (2) passes through the communication hole (17) and the inner pipe insertion through hole (19) of the second connector member (12). In the state where the tip portion is fitted into the large diameter portion (15) for fitting the inner tube of the first connector member (11), the first connector member (11) and the second connector member (12) For example, it joins by brazing, and the 1st fluid channel | path (6) of a heat exchange part (2) is connected to the 1st flow path (13) via the communicating hole (14) by this. Further, the outer tube (4) of the heat exchange part (2) is fitted into the outer tube fitting large-diameter part (18) of the second connector member (12), and the second connector member (12). For example, the second fluid passage (7) of the heat exchange section (2) is connected to the second flow path (16) through the communication hole (17). . In this way, both end portions of the heat exchange section (2) are connected to both connectors (3).

As shown in FIG. 4, the heat exchanger (1) includes a compressor (21), a gas cooler (22), an evaporator (23), an accumulator (24) as a gas-liquid separator, and an expansion valve (25 ) And a supercritical refrigeration cycle using a supercritical refrigerant composed of CO _2, a high-temperature and high-pressure refrigerant coming out of the gas cooler (22) and a low-temperature and low-pressure coming out of the evaporator (23) and passing through the accumulator (24) It is suitably used as an intermediate heat exchanger for exchanging heat with other refrigerants. The supercritical refrigeration cycle is mounted on a vehicle such as an automobile as a car air conditioner.

  In the supercritical refrigeration cycle described above, a pipe pipe (26) extending from the gas cooler (22) is connected to the first connector member (11) of one of the heat exchangers (1), here the left connector (3). A pipe pipe (27) extending to the expansion valve (25) is connected to the first connector member (11) of the right connector (3), and connected to the flow path (13). Connected to lead to the road (13). Also, one of the heat exchangers (1), here, the second connector member (12) of the right connector (3), and a pipe (28) extending from the accumulator (24) are connected to the second flow path (16). On the other hand, a pipe (29) for piping extending to the compressor (21) is connected to the second flow path (16) to the second connector member (12) of the left connector (3). It is connected to the.

  In this supercritical refrigeration cycle, the high-temperature and high-pressure refrigerant compressed by the compressor (21) passes through the gas cooler (22), passes through the piping pipe (26), and the first connector member (11) of the left connector (3). ) Enters the first fluid passage (6) of the heat exchange section (2) through the communication hole (14) and passes through the first fluid passage (6) to the right. Flow into the first flow path (13) of the first connector member (11) of the right connector (3) through the communication hole (14), and through the pipe (27) for the expansion valve ( Sent to 25).

  On the other hand, the low-temperature and low-pressure refrigerant sent from the accumulator (24) through the piping pipe (28) flows into the second flow path (16) of the second connector member (12) of the right connector (3). Through the communication hole (17) and into the second fluid passage (7) of the heat exchanging section (2), to the left in the second fluid passage (7), and through the communication hole (17). It flows into the second flow path (16) of the second connector member (12) of the left connector (3), and is sent to the compressor (21) through the piping pipe (29).

  The high-temperature and high-pressure refrigerant coming out of the gas cooler (22) flowing in the first fluid passage (6) of each heat exchange section (2) of the heat exchanger (1) and the second fluid passage (7) The low-temperature and low-pressure refrigerant that has left the flowing evaporator (23) and has passed through the accumulator (24) exchanges heat, and the high-temperature and high-pressure refrigerant is cooled.

  FIG. 5 shows another embodiment of the heat exchanger according to the present invention.

  In the case of the heat exchanger (30) shown in FIG. 5, the number of heat exchange parts (2) is larger than that in the case of the heat exchanger (1) shown in FIG. Therefore, the total heat transfer area between the refrigerant flowing in the first fluid passage (6) of all the heat exchange sections (2) and the refrigerant flowing in the second fluid passage (7) is shown in FIG. When equal to the exchanger (1), the length L1 in the left-right direction can be made shorter than the length L2 in the left-right direction of the heat exchanger (1) in FIG. Other configurations are the same as those of the heat exchanger (1) shown in FIG. 1, and the same parts and the same parts are denoted by the same reference numerals and redundant description is omitted.

Similarly to the heat exchanger (1) shown in FIG. 1, the heat exchanger (30) is also composed of a compressor (21), a gas cooler (22), an evaporator (23), an accumulator (24) as a gas-liquid separator, and A supercritical refrigeration cycle that uses a supercritical refrigerant composed of CO ₂ together with an expansion valve (25) as a pressure reducer is constructed, and an accumulator (23) exits from the high-temperature and high-pressure refrigerant and evaporator (23) that come out from the gas cooler (22). It is suitably used as an intermediate heat exchanger for exchanging heat with a low-temperature and low-pressure refrigerant that has passed through 24). The supercritical refrigeration cycle indicates a supercritical refrigeration cycle mounted on a vehicle such as an automobile as a car air conditioner.

In the above two embodiments, CO ₂ is used as the supercritical refrigerant in the supercritical refrigeration cycle, but is not limited to this, and ethylene, ethane, nitric oxide and the like are used.

  In the above two embodiments, the connector is formed by two block-shaped connector members. However, the present invention is not limited to this, and a connector in which the first and second flow paths are formed in one block. It may be used.

  Further, in the two embodiments, the heat exchangers (1) and (30) are used as intermediate heat exchangers in the supercritical refrigeration cycle, but the present invention is not limited to this, and the use thereof can be changed as appropriate. is there.

1 is a partially cutaway front view showing an overall configuration of an embodiment of a heat exchanger according to the present invention. It is the elements on larger scale of FIG. It is the III-III sectional view taken on the line of FIG. It is the schematic which shows the supercritical refrigerating cycle which used the heat exchanger shown in FIG. 1 as an intermediate heat exchanger. It is a partially notched front view which shows the whole structure of other embodiment of the heat exchanger by this invention.

Explanation of symbols

(1) (30): Heat exchanger
(2): Heat exchange section
(3): Connector
(4): Outer pipe
(5): Inner pipe
(5a): Outward protrusion
(6): First fluid passage
(7): Second fluid passage
(8): Heat transfer fin
(11): First connector member
(12): Second connector member
(13): First flow path
(16): Second flow path
(21): Compressor
(22): Gas cooler
(23): Evaporator
(24): Accumulator (gas-liquid separator)

Claims (16)

A plurality of heat exchanging units arranged in parallel and a pair of connectors arranged at intervals and connected to both ends of all the heat exchanging units. A first fluid passage having a first fluid passage and a second fluid passage formed around the first fluid passage, wherein each connector communicates the first fluid passages of all the heat exchange sections to the outside; The heat exchanger which has the 2nd flow path which makes the 2nd fluid channel | path of all the heat exchange parts independent with respect to a path | route outside. The heat exchanger according to claim 1, wherein heat transfer fins are provided in the second fluid passage of the heat exchange unit. The heat exchange part is formed by an outer tube and an inner tube arranged in the outer tube at an interval. The inner tube serves as a first fluid passage, and a gap between the outer tube and the inner tube is provided. The heat exchanger according to claim 1 or 2, wherein the heat exchanger is a second fluid passage. The heat exchanger according to claim 3, wherein heat transfer fins are integrally formed on the outer peripheral surface of the inner tube so as to be spaced apart in the circumferential direction and extend in the length direction of the inner tube. The heat exchanger according to claim 3 or 4, wherein the outer tube, the inner tube, and the connector are made of aluminum. The heat exchanger according to claim 5, wherein the outer tube and the inner tube are made of an aluminum extruded shape. The heat exchanger according to claim 1, wherein each connector is formed by a first connector member having a first flow path and a second connector member having a second flow path. The heat exchange part is formed by an outer tube and an inner tube arranged in the outer tube at an interval. The inner tube serves as a first fluid passage, and a gap between the outer tube and the inner tube is provided. The second fluid passage is provided, the first connector member is disposed on the outer side in the length direction of the heat exchange part than the second connector member, and both end portions of the inner tube are protruded outward from both ends of the outer tube. The heat exchanger according to claim 7, wherein the outer projecting portion of the inner tube is connected to the first connector member in a state of passing through the second connector member, and the outer tube is connected to the second connector member. The heat exchanger according to claim 8, wherein heat transfer fins are provided in the second fluid passage. The heat exchanger according to claim 9, wherein the heat transfer fins are integrally formed on the outer peripheral surface of the inner tube so as to be spaced apart in the circumferential direction and extend in the length direction of the inner tube. The heat exchanger according to any one of claims 8 to 10, wherein the first and second connector members, the outer tube, and the inner tube are made of aluminum. The heat exchanger according to claim 11, wherein the outer tube and the inner tube are made of extruded aluminum. A supercritical refrigerant comprising a compressor, a gas cooler, an evaporator, a gas-liquid separator, and an intermediate heat exchanger that exchanges heat between the refrigerant that has come out of the gas cooler and the refrigerant that has come out of the evaporator and has passed through the gas-liquid separator. A supercritical refrigeration cycle in which the intermediate heat exchanger is a heat exchanger according to any one of claims 1 to 12. The high-pressure refrigerant that has come out of the gas cooler flows in the first fluid passage of the intermediate heat exchanger, and the low-pressure refrigerant that has also passed through the gas-liquid separator in the second fluid passage has passed through the second fluid passage. The supercritical refrigeration cycle according to claim 13. The supercritical refrigeration cycle according to claim 13 or 14, wherein the supercritical refrigerant comprises carbon dioxide. A vehicle on which the supercritical refrigeration cycle according to any one of claims 13 to 15 is mounted as a car air conditioner.

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