CN116235017A - Heat exchanger with means for reducing thermal stresses - Google Patents

Heat exchanger with means for reducing thermal stresses Download PDF

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Publication number
CN116235017A
CN116235017A CN202180063996.9A CN202180063996A CN116235017A CN 116235017 A CN116235017 A CN 116235017A CN 202180063996 A CN202180063996 A CN 202180063996A CN 116235017 A CN116235017 A CN 116235017A
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CN
China
Prior art keywords
heat exchange
heat exchanger
partition wall
flow
tank
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202180063996.9A
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Chinese (zh)
Inventor
韩至勋
赵柄善
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Hanon Systems Corp
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Hanon Systems Corp
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Filing date
Publication date
Priority claimed from KR1020210123159A external-priority patent/KR20220037982A/en
Application filed by Hanon Systems Corp filed Critical Hanon Systems Corp
Publication of CN116235017A publication Critical patent/CN116235017A/en
Pending legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F28D1/0408—Multi-circuit heat exchangers, e.g. integrating different heat exchange sections in the same unit or heat exchangers for more than two fluids
    • F28D1/0426—Multi-circuit heat exchangers, e.g. integrating different heat exchange sections in the same unit or heat exchangers for more than two fluids with units having particular arrangement relative to the large body of fluid, e.g. with interleaved units or with adjacent heat exchange units in common air flow or with units extending at an angle to each other or with units arranged around a central element
    • F28D1/0435—Combination of units extending one behind the other
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F28D1/053—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight
    • F28D1/0535—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight the conduits having a non-circular cross-section
    • F28D1/05366—Assemblies of conduits connected to common headers, e.g. core type radiators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/0202—Header boxes having their inner space divided by partitions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/0202—Header boxes having their inner space divided by partitions
    • F28F9/0204—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions
    • F28F9/0214—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions having only longitudinal partitions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/0219—Arrangements for sealing end plates into casing or header box; Header box sub-elements
    • F28F9/0224—Header boxes formed by sealing end plates into covers
    • F28F9/0226—Header boxes formed by sealing end plates into covers with resilient gaskets
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/026—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits
    • F28F9/028—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits by using inserts for modifying the pattern of flow inside the header box, e.g. by using flow restrictors or permeable bodies or blocks with channels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/008—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for vehicles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/008—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for vehicles
    • F28D2021/0089—Oil coolers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/008—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for vehicles
    • F28D2021/0091—Radiators
    • F28D2021/0094—Radiators for recooling the engine coolant
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2270/00—Thermal insulation; Thermal decoupling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/0202—Header boxes having their inner space divided by partitions
    • F28F9/0204—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions
    • F28F9/0207—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions the longitudinal or transversal partitions being separate elements attached to header boxes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/0202—Header boxes having their inner space divided by partitions
    • F28F9/0204—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions
    • F28F9/0209—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions having only transversal partitions
    • F28F9/0212—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions having only transversal partitions the partitions being separate elements attached to header boxes

Abstract

The invention relates to a heat exchanger with means for reducing thermal stresses. It is an object of the present invention to provide an integrated heat exchanger for cooling two heat exchange media having different temperatures, which heat exchanger has means for reducing thermal stresses and has flow distributing structures in the tank for efficient distribution of thermal stresses caused by temperature differences.

Description

Heat exchanger with means for reducing thermal stresses
Technical Field
The present invention relates to a heat exchanger, and more particularly, to an integrated heat exchanger configured to cool two types of heat exchange media having different temperatures, i.e., a heat exchanger having a means for reducing thermal stress, which can effectively disperse thermal stress caused by a temperature difference.
Background
In general, not only components such as an engine for operating a vehicle but also various heat exchangers such as a radiator, an intercooler, an evaporator, and a condenser for cooling components such as an engine in a vehicle or adjusting the air temperature in the interior of a vehicle are provided in an engine room of a vehicle. Typically, the heat exchange medium flows in a heat exchanger. The heat exchange medium in the heat exchanger exchanges heat with outside air existing outside the heat exchanger, so that a cooling operation or heat dissipation is performed.
In most cases, a single type of heat exchange medium flows in the heat exchanger. However, a heat exchanger in which two types of heat exchange media flow is sometimes integrated as needed. For example, in the case of a radiator and an oil cooler of a vehicle, a coolant for cooling an engine flows in the radiator, and an oil such as engine oil or transmission oil flows in the oil cooler. Of course, the radiator and the oil cooler are sometimes constructed as separate devices. However, in order to improve the space utilization of the engine room, the radiator and the oil cooler are generally integrated into a structure such as a water-cooled oil cooler structure configured to cool oil by using a coolant.
The portion of the heat exchanger where heat exchange is mainly performed is a portion where tubes are stacked, and this portion is generally referred to as a core of the heat exchanger. In the related art, an integrated heat exchanger in which two types of heat exchange media flow generally has a structure in which cores in which the heat exchange media flow are connected in series. Meanwhile, a structure in which cores are connected in parallel has been recently sometimes employed. Fig. 1 shows an example of an integrated heat exchanger in the related art having a structure in which cores in which two types of heat exchange media flow are connected in parallel. In the case of the integrated heat exchanger according to the example shown in fig. 1, the structure in which the two cores are connected in parallel with each other is similar to that of a heat exchanger in which a single type of heat exchange medium flows. In more detail, the heat exchangers are arranged in two rows, and a partition is provided in the header tank to isolate the heat exchange medium. The construction of the two-row heat exchanger is well disclosed in korean patent No.0825709 ("heat exchanger", 22 nd year, 2008).
Specifically, the heat exchanger 100 includes: a pair of header tanks 100 spaced apart from each other by a predetermined distance and disposed side by side; and a plurality of tubes 200 each having two opposite ends fixed to the header tank 100 and configured to define a flow path for a refrigerant, and the heat exchanger 100 further includes a plurality of fins interposed between the tubes 200. In this case, the tubes 200 are arranged in two rows in the forward/backward direction. The header tanks 100 each include a partition wall 125 extending in the longitudinal direction in the header tank to partition a space communicating with the corresponding tube. Accordingly, the first heat exchange medium and the second heat exchange medium flowing in the tubes 200 arranged in the first and second rows, respectively, can be isolated and flowed without being brought together. Of course, pairs of inlet and discharge ports are provided for each heat exchange medium in header 100, respectively. Fig. 1 shows that the first and second inlet ports and the first and second discharge ports are arranged in the header tank in opposite directions in a cross-flow manner, wherein the heat exchange medium flows in one direction. However, in the case of a U-shaped flow in which the heat exchange medium flows in a U-shape, the first and second inlet ports and the first and second discharge ports may be provided in the header tank in the same direction.
In the integrated heat exchanger provided as described above, two types of heat exchange media different in properties such as coolant and oil may flow, or two types of heat exchange media different in temperature range such as low-temperature coolant and high-temperature coolant may flow, so that the integrated heat exchanger operates in various ways. In any case, since the temperature ranges of the heat exchange media are very different in the case of the two types of heat exchange media flowing, a significant temperature difference is defined between the front core and the rear core. When the temperature distribution is unbalanced as described above, the degree of thermal deformation varies depending on the position. For this reason, there are problems in that: thermal stresses are concentrated at specific locations of the heat exchanger. In the case of the above-described integrated heat exchanger, the thermal stress is concentrated highest at the portion where the front core and the rear core are separated. Because thermal stress concentration caused by thermal deformation is a major factor causing damage or destruction of the heat exchanger, a design for coping with thermal stress concentration is required.
[ related art literature ]
[ patent literature ]
1. Korean patent No.0825709 (heat exchanger, 2008, 4, 22 days)
Disclosure of Invention
Technical problem
Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the related art, and an object of the present invention is to provide an integrated heat exchanger configured to cool two types of heat exchange media having different temperatures, i.e., a heat exchanger having a means for reducing thermal stress, which can effectively disperse thermal stress caused by a temperature difference.
Technical proposal
In order to achieve the above object, a heat exchanger 1000 according to the present invention includes: a pair of header tanks 100 each having a fluid flow space defined therein by coupling the header 110 and the tank 120, the pair of header tanks being spaced apart from each other by a predetermined distance and disposed side by side; and a plurality of tubes 200 each having two opposite ends fixed to the header tank 100 and configured to define a flow path for the heat exchange medium, the plurality of tubes being arranged in two rows in the forward/backward direction, wherein an inner space of the header tank 100 is partitioned and divided into a front heat exchange portion and a rear heat exchange portion by a partition wall 125, wherein the heat exchange medium having different average temperatures flows in the front heat exchange portion and the rear heat exchange portion, respectively, and wherein the partition wall 125 has a thermal stress reducing means.
As one embodiment of the thermal stress reducing means, the thermal stress reducing means may be a flow distribution structure formed on the tank 120 in a region near a partition wall adjacent to the partition wall 125, which is a boundary line between the front heat exchange portion and the rear heat exchange portion, and the flow distribution structure may be formed such that a flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the region near the partition wall is relatively lower than a flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the remaining region.
In this case, the flow distribution structure may be a flow rate adjustment baffle 121, one end of which is fixed to the inner surface of the tank 120 and the other end of which is disposed to be spaced apart from the inner space of the tube 200, the flow rate adjustment baffle being formed to reduce the flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the region near the partition wall.
Alternatively, the flow distribution structure may be a flow rate adjustment rib 122 formed as a part of the tank 120, which protrudes to the inside of the header tank 100, and the end of the protruding portion is disposed to be spaced apart from the inner space of the tube 200, and the flow rate adjustment rib may be formed to reduce the flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the region near the partition wall.
Further, the flow distributing structure may be formed in one of the front heat exchanging portion and the rear heat exchanging portion in which the temperature of the heat exchanging medium is relatively high. More specifically, in the heat exchanger 1000, the temperature of the heat exchange medium flowing in the rear heat exchange portion may be higher than the temperature of the heat exchange medium flowing in the front heat exchange portion, and the flow distribution structure of the heat exchanger may be formed in the rear heat exchange portion.
Furthermore, the flow distribution structure may be applied to all positions of the tube 200.
Further, the flow distributing structure may be formed to be spaced apart only from a position opposite to the position of the tube 200.
The flow distribution structure may be formed to correspond to a range of 10% to 20% of the width of the tube 200.
As another embodiment of the thermal stress reducing means, the thermal stress reducing means may be an air pocket 123 formed in the form of an empty space in the partition wall 125.
In this case, the air pocket 123 may extend in the extending direction of the partition wall 125.
Further, the air pocket 123 may be formed to be opened at an end directed toward the header 120.
In this case, the opening portion of the air pocket 123 may be sealed by a gasket 150 provided at a portion where the header 110 and the tank 120 are coupled.
In addition, in this case, the gasket 150 may have a sealing protrusion 151 protruding at a position corresponding to the opening portion of the air pocket 123.
In addition, the heat exchanger 1000 may have a leak check path 124 formed in the tank 120 and provided in the form of a flow path allowing the air pocket 123 to communicate with the outside.
Further, the heat exchanger 1000 may be a radiator in which a high-temperature coolant and a low-temperature coolant flow.
Advantageous effects
According to the present invention, in an integrated heat exchanger configured to cool two types of heat exchange media having different temperatures, a flow distribution structure is provided in a tank, or air pockets are formed in a partition wall in the tank, which makes it possible to effectively disperse thermal stress caused by a temperature difference. More specifically, in the heat exchanger of the present invention, the core of the heat exchanger includes a front core and a rear core for cooling two types of heat exchange media, and it is known that thermal stress is concentrated highest at a boundary portion between the front core and the rear core. In this case, in the present invention, as one embodiment, the thermal stress concentration is reduced by adopting a structure in which the flow rate is reduced by partially blocking the end portions of the pipes at the boundary portions where the pipes are disposed adjacent to each other. In particular, in the present invention, the flow distribution is achieved by a baffle or a tank inward protruding structure formed adjacent to a partition wall formed in the tank. Alternatively, as another embodiment, air pockets are formed in the partition wall such that heat insulation is effectively achieved between the front side and the rear side.
Since the flow distribution structure is provided as described above, the temperature gradient at the boundary portion is more gently defined during the process in which the heat exchange medium having different temperature ranges flows in the front core and the rear core, which enables the problem of temperature imbalance to be solved. Of course, thermal stresses can be effectively dispersed, thereby ultimately preventing the problem of damage and breakage of the connection between the header and the tube.
Drawings
Fig. 1 is a diagram showing an example of an integrated heat exchanger in the related art.
Fig. 2 is a perspective view of a first embodiment of the integrated heat exchanger tank structure of the present invention.
Fig. 3 is a cross-sectional view of a first embodiment of the integrated heat exchanger tank structure of the present invention.
Fig. 4 is a perspective view of a second embodiment of the integrated heat exchanger tank structure of the present invention.
Fig. 5 is a cross-sectional view of a second embodiment of the integrated heat exchanger tank structure of the present invention.
Fig. 6 is a diagram of an example of a temperature gradient in the related art and the present invention.
Fig. 7 is a graph for comparing temperature gradients between the related art and the present invention.
Fig. 8 is a diagram showing deformation of the baffle plate caused when the temperature difference between the heat exchange media at both sides of the integrated heat exchanger is large.
Fig. 9 is a cross-sectional view of a third embodiment of the integrated heat exchanger tank structure of the present invention.
Fig. 10 is a cross-sectional view of a fourth embodiment of the integrated heat exchanger tank structure of the present invention.
Description of the reference numerals
1000: heat exchanger
100: header box
110: header 120: box (BW)
121: flow distributing baffle 122: flow distributing rib
123: air pocket 124: leak check path
125: partition wall
150: gasket 155: sealing protrusion
200: pipe
Detailed Description
Hereinafter, a heat exchanger constructed according to the present invention will be described in detail with reference to the accompanying drawings.
The heat exchanger described in the present invention is an integrated heat exchanger configured such that different types of heat exchange media having different temperatures flow independently, particularly a heat exchanger in which tubes are arranged in two front and rear rows, and cores, i.e., heat exchange members (where heat exchange is mainly performed) are doubly provided at the front and rear sides. Specifically, as briefly described with reference to fig. 1, the heat exchanger 1000 may include: a pair of header tanks 100 each having a fluid flow space defined therein by coupling the header 110 and the tank 120, the pair of header tanks 100 being spaced apart from each other by a predetermined distance and disposed side by side; and a plurality of tubes 200 each having two opposite ends fixed to the header tank 100 and arranged in two rows in the forward/backward direction while defining a flow path for the heat exchange medium. In addition, the heat exchanger 1000 may further include a plurality of fins interposed between the tubes 200.
In this case, in the heat exchanger 1000, the inner space of the header tank 100 is partitioned and isolated by the partition wall 125 in the forward/backward direction so that heat exchange media having different average temperatures flow in the front heat exchange portion and the rear heat exchange portion, respectively. That is, the heat exchanger is shaped like a common two-row heat exchanger. Since the partition wall 125 completely isolates the front heat exchange portion and the rear heat exchange portion, different heat exchange mediums can flow in the front heat exchange portion and the rear heat exchange portion independently. For example, a radiator or the like in which a high-temperature coolant and a low-temperature coolant flow may be used as a heat exchanger configured such that different types of heat exchange media having different average temperatures flow for the respective regions. In this case, the high temperature coolant may be used to remove heat from the engine while flowing through a coolant circuit that includes the engine. The low-temperature coolant may be used to cool electrical components having a relatively low temperature while flowing through a coolant loop including the electrical components.
In the above heat exchanger, the degree of thermal expansion is, of course, different between the portion where the high-temperature heat exchange medium flows and the portion where the low-temperature heat exchange medium flows. When the degree of thermal expansion is uniform in all the components of the heat exchanger in a state in which the components of the heat exchanger are firmly fixed to each other by welding, there is no great problem. However, in the case where portions having greatly different degrees of thermal expansion are locally formed, thermal stress is naturally and excessively concentrated at the corresponding portions, which results in damage. In the case of the heat exchanger 1000 of the present invention, the portion near the partition wall 125, which is the boundary line between the front heat exchange portion and the rear heat exchange portion, is the portion where the thermal stress is most concentrated.
The present invention aims to reduce thermal stress concentration at this portion. Since the temperature range conditions of the heat exchange medium (which flows in the front heat exchange portion and the rear heat exchange portion, respectively) cannot be changed, the phenomenon of thermal stress concentration cannot be removed. However, it is expected that the thermal stress concentration may be further reduced at a level at which the temperature range is rapidly changed before and after the boundary line is further reduced (i.e., in a case where the temperature range is more gently changed in the vicinity of the boundary line).
That is, in the present invention, the partition wall 125 has a thermal stress reducing means, thereby solving the above-described problem. In this case, as one embodiment, the thermal stress reducing means may be a flow distributing structure. As another embodiment, the thermal stress reduction device may be an air pocket. The flow distribution structure and cavitation will be described in more detail.
[1] One embodiment of the thermal stress reduction device: flow distribution structure
As one embodiment of the thermal stress reducing means, in the present invention, a flow distributing structure is formed on the tank 120 in a region near the partition wall adjacent to the partition wall 125, the partition wall 125 being a boundary line between the front heat exchanging portion and the rear heat exchanging portion, thereby reducing the flow rate of the heat exchanging medium. More specifically, the flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the region near the partition wall is relatively lower than the flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the remaining region. With the above configuration, the amount of the heat exchange medium present in the region near the partition wall can be reduced, so that the temperature gradient is more gently changed, and thus the thermal stress concentration can be further reduced. That is, the flow distributing structure acts as a thermal stress reducing means.
Fig. 2 is a perspective view of a first embodiment of the integrated heat exchanger tank structure of the present invention, and fig. 3 is a cross-sectional view of the first embodiment of the integrated heat exchanger tank structure of the present invention. (for reference, a general gasket is also provided at a portion where the header 110 and the tank 120 are coupled for sealability, however, for simplification of the drawing, the gasket is omitted from the perspective view of fig. 2, and a gasket 150 is shown in fig. 3.) in the first embodiment, the flow distributing structure is configured as a flow rate adjusting baffle 121, one end portion of the flow rate adjusting baffle 121 is fixed to the inner surface of the tank 120, and the other end portion is spaced apart from the inner space of the tube 200, and the flow rate adjusting baffle 121 is configured to reduce the flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the vicinity of the partition wall. As shown in fig. 3, the other end portion of the flow rate adjustment baffle 121 is shown to be spaced upward from the end portion of the tube 200 by a predetermined distance and to cover an opening portion of a portion of the end portion of the tube 200, but the present invention is not limited thereto. For example, the other end of the flow rate adjustment baffle 121 may extend to the inner space of the tube 200. In this case, the outer diameter of the other end portion of the flow rate adjustment baffle 121 may be slightly smaller than the inner diameter of the tube 200. That is, in this case, the other end portion of the flow rate adjustment baffle 121 is fitted into the inner space of the tube 200 while defining a small gap. Accordingly, the flow rate can be reduced by reducing the area of the flow path. Meanwhile, the flow rate adjustment baffle 121 is a structure fixed to the tank 120, and may be integrated with the tank 120 by being manufactured using a single mold. As shown in fig. 3, one end of the flow rate adjustment baffle 121 may extend to and be connected to a ceiling of an inner surface of the tank 120 in view of manufacturing convenience.
Fig. 4 is a perspective view of a second embodiment of the integrated heat exchanger tank structure of the present invention, and fig. 5 is a cross-sectional view of the second embodiment of the integrated heat exchanger tank structure of the present invention. (even in this case, like fig. 2 and 3, the gasket is omitted from fig. 4, and the gasket 150 is shown in fig. 5.) in the second embodiment, the flow distributing structure is configured to be formed as a flow rate regulating rib 122 that protrudes toward the inside of the header tank 100 as a part of the tank 120, and the end of the protruding portion is disposed to be spaced apart from the inner space of the pipe 200. The flow rate adjustment rib 122 is formed to reduce the flow rate of the heat exchange medium flowing in the inner space of the tube 200 in the region near the partition wall. Unlike the first embodiment in which the flow rate adjustment baffle 121 is constructed as a separate member and assembled to the tank 120, the flow rate adjustment rib 122 may be integrated with the tank 120 as shown. As with the flow rate adjustment baffle 121, the flow rate adjustment rib 122 is also formed to cover an opening portion of a portion of the end of the tube 200, thereby reducing the flow rate of the heat exchange medium flowing into the inner space of the tube 200.
The flow distribution structure may be formed on one of the front heat exchange portion and the rear heat exchange portion in which the temperature of the heat exchange medium is relatively high. This is because as the temperature of the heat exchange medium increases, the degree of thermal expansion increases, and the amount of thermal stress concentration increases. The drawing shows that the temperature of the heat exchange medium flowing in the rear heat exchange section is higher than that of the heat exchange medium flowing in the front heat exchange section, and that a flow distributing structure is formed in the rear heat exchange section. It is assumed that the direction in which the outside air is blown inward is defined as the forward direction, and the direction in which the outside air is blown outward is defined as the backward direction. In the case where the heat exchange medium having a higher temperature flows in the front heat exchange portion, the air passing through the front heat exchange portion has absorbed excessive heat. For this reason, the air cannot sufficiently absorb heat in the rear heat exchange portion, which may cause a problem in that heat exchange performance is deteriorated in the rear heat exchange portion. In view of the above, the heat exchange medium having a higher temperature generally flows in the rear heat exchange portion in the heat exchanger in which the heat exchange portions are disposed in parallel in the forward/backward direction. That is, from a general design trend, a flow distribution structure may be formed in the rear heat exchange portion.
Meanwhile, in the present invention, since thermal stress concentration occurs over the entire front and rear heat exchange portions, the flow distribution structure may be applied to all positions of the tube 200. Further, the flow distributing structure may be formed to be spaced apart only from a position opposite to the position of the tube 200 in order to prevent the flow distributing structure from excessively occupying the inner space of the header tank 100.
Further, the flow distribution structure may be formed such that the degree to which the flow of the heat exchange medium is reduced at the position of the tube 200 is equal to each other. That is, the ends of the tubes 200 are covered to the same extent as each other with respect to all the tubes 200. However, the present invention is not necessarily limited thereto. This configuration will be described in detail. In the heat exchange portion, the temperature is reduced during a process in which a high-temperature heat exchange medium is introduced into the inlet port and exchanges heat with external air while flowing through the heat exchange portion. The heat exchange medium having a low temperature as described above is discharged to the discharge port. That is, even in a single heat exchange portion, the temperature of the heat exchange medium at the inlet port is relatively high, and the temperature of the heat exchange medium at the discharge port is relatively low. In this case, it is assumed that the high-temperature heat exchange portion in which the high-temperature heat exchange medium having a high average temperature flows is disposed in parallel with the low-temperature heat exchange portion in which the low-temperature heat exchange medium having a low average temperature flows. According to the above principle, in each of the high-temperature heat exchange portion and the low-temperature heat exchange portion, the temperature at the inlet port is the highest, and the temperature at the discharge port is the lowest. In this case, in the case where the side of the discharge port of the high-temperature heat exchange portion (the portion at which the temperature is lowest in the high-temperature heat exchange portion) and the side of the inlet port of the low-temperature heat exchange portion (the portion at which the temperature is highest in the low-temperature heat exchange portion) are disposed adjacent to each other, the temperature difference between the high-temperature heat exchange portion and the low-temperature heat exchange portion does not occur greatly in the above-described side. Meanwhile, with the above-described configuration, at the opposite side, the side of the inlet port of the high-temperature heat exchange portion (the portion having the highest temperature in the high-temperature heat exchange portion) and the side of the discharge port of the low-temperature heat exchange portion (the portion having the lowest temperature in the low-temperature heat exchange portion) are disposed adjacent to each other. In this case, a maximum temperature difference may occur. In this case, it is possible to design such that the flow rate of the heat exchange medium can be further reduced by increasing the degree to which the tube is covered at the portion where the temperature difference is large, and the flow rate of the heat exchange medium can be reduced less by decreasing the degree to which the tube is covered at the portion where the temperature difference is small. That is, as described above, the flow distribution structure may be formed such that the degree to which the flow of the heat exchange medium is reduced at the position of the tube 200 is different from each other.
Fig. 6 shows an example of a temperature gradient in the related art and the present invention. Similar to the context described above with reference to the heat exchange sections according to the arrangement of temperatures in the common two-row heat exchanger, in the embodiment of fig. 6 the temperature of the heat exchange medium flowing in the rear heat exchange section is higher than the temperature of the heat exchange medium flowing in the front heat exchange section. That is, the temperature of the rear tube is higher than that of the front tube. As shown in the diagram of the left side < related art >, there is a significantly large temperature difference between the front side and the rear side in the region near the partition wall. Meanwhile, as shown in the graph of < present invention > on the right side, it can be seen that the temperature difference spectrum between the front side and the rear side in the region near the partition wall is widely distributed, that is, the temperature is changed more gently than < related art >.
Fig. 7 is a graph for comparing temperature gradients between the related art and the present invention, i.e., a graph showing the results of fig. 6. The graph of < related art > is indicated by a dotted line, and the graph of < present invention > is indicated by a solid line. As appropriately shown in fig. 7, in the case of < related art > in which the flow distribution structure is not provided, there is a portion in which the temperature gradient is rapidly curved. In contrast, in the case of < the present invention > in which the flow distribution structure is provided, it can be seen that the portion of the < related art > which is rapidly bent has a significantly stepwise shape. Since the temperature gradient is gently formed as described above, the degree of thermal expansion can also be gently changed. Accordingly, thermal stress concentration can be further reduced and reduced as compared with the related art.
At the same time, the flow distribution structure thus reduces the flow rate of the heat exchange medium by covering a portion of the tubes and prevents the heat exchange medium from flowing into the tube wells. In the case that the flow distribution structure is excessively large, the flow distribution structure adversely affects the total flow of the heat exchange medium, which may deteriorate the heat exchange performance. In view of this, the flow distribution structure is preferably not excessively large. In contrast, in the case where the flow distribution structure is excessively small, the above-described effect of reducing the thermal stress concentration cannot be obtained. In view of the above and the aspects shown in the graph of fig. 7, the flow distribution structure may be formed to correspond to a range of 10% to 20% of the width of the tube 200.
[2] Another embodiment of the thermal stress reduction device: cavitation of air
In the above-described present invention, when the heat exchange medium having different temperatures flows in the two spaces of the header tank divided by the partition wall, with the flow distributing structure of the present invention, it is made possible to solve the problem of rapid change in temperature gradient at the periphery of the partition wall and the problem of thermal stress concentration caused by rapid change in the degree of thermal expansion. In the related art, the temperature difference between the heat exchange mediums flowing in the two spaces of the header tank cannot be excessively increased due to the problem of thermal stress concentration. However, compared with the related art, the temperature difference between the heat exchange mediums can be designed and further increased by adopting the present invention.
However, in this case, the temperature difference between the members between which the partition wall is interposed is excessively large, which may cause a problem in that significant unnecessary and undesired heat transfer occurs between the heat exchange mediums passing through the partition wall. Further, when the temperature difference of the two opposite sides of the partition wall is excessively large, the degree of thermal expansion at the two opposite sides of the partition wall may be significantly unbalanced. Meanwhile, in general, in the heat exchanger header tank, in addition to the partition wall extending in the longitudinal direction of the header tank, a baffle extending in the direction of the cross section of the header tank is often provided in order to adjust the flow path of the heat exchange medium. However, when the degree of thermal expansion at the two opposite sides of the partition wall is different in the two rows of header tanks, there is a problem in that the baffle plate formed to be suitable for the internal shape of the header tanks is deformed, or the baffle plate and the tank are separated. Fig. 8 is a diagram showing an example of deformation of the baffle plate caused when the temperature difference between the heat exchange media at two opposite sides of the integrated heat exchanger is large. When a gap is formed between the baffle 130 and the tank 120, the heat exchange medium flows into an undesired space, which causes a problem in that the designed heat exchange performance cannot be obtained.
The third embodiment is provided to prevent the problem that, in the case where the temperature difference between the two opposite sides of the partition wall 125 is excessively large, the baffle 130 is deformed and distorted due to the difference in the degree of thermal expansion between the two opposite surfaces. Fig. 9 is a cross-sectional view of a third embodiment of the integrated heat exchanger tank structure of the present invention. As shown, in the third embodiment, the air pocket 123 is formed in the form of an empty space in the partition wall 125 or on the partition wall 125. As shown, the air pocket 123 may extend in the extending direction of the partition wall 125. Inside the air pocket 123 is an empty space filled with air, which can effectively prevent unnecessary heat transfer through the partition wall 125. That is, in the present embodiment, the air pocket 123 is a thermal stress reducing means.
In addition, the air pocket 123 may be applied to a heat exchanger having the above-described flow distribution structure. However, only the air pocket 123 may be applied without a flow distributing structure. Even in this case, the heat insulating effect can alleviate the thermal stress concentration in the vicinity of the boundary line between the front side and the rear side. That is, the heat exchanger 1000 of the present invention may suitably and selectively employ one or both of the flow distribution structure described in [1] and the air pocket described in [2] as the thermal stress reducing means.
Meanwhile, the air pocket 123 may be provided in the partition wall 125 only in the form of an empty space. In the case of manufacturing the tank 120 by pultrusion, there is no problem in forming the shape of the air pocket 123. However, in consideration of the problem that the defect rate increases when the shape complexity increases, the air pocket 123 may be opened at the end directed toward the header 120, as shown in fig. 9. Because the partition wall 125 and the end of the air pocket 123 directed toward the header 120 are completely sealed by the gasket 150 in any manner, the configuration in which the end of the air pocket 123 directed toward the header 120 is opened does not affect the function of the partition wall 125 (the function of isolating the flow space of the heat exchange medium in the forward/rearward direction). That is, the open portion of the air pocket 123 is sealed by the gasket 150. In this case, the gasket 150 may have a sealing protrusion 151 protruding at a position corresponding to the opening portion of the air pocket 123, so as to more firmly secure the sealability of the opening portion of the air pocket 123. The sealing protrusion 151 may be inserted into the opening portion of the air pocket 123 so that the air pocket 123 may be firmly sealed. Further, since the opening portion of the air pocket 123 naturally guides the sealing protrusion 151 during the insertion process, the sealing protrusion 151 also serves to prevent the gasket 150 from deviating from a precise position and from being erroneously assembled when the gasket 150 is assembled.
Meanwhile, a first embodiment of the flow distribution structure shown in fig. 2 and 3 is shown in fig. 9, but the present invention is not limited thereto. The air pocket 123 of the third embodiment is applicable to the second embodiment. Alternatively, of course, the air pocket 123 may be applied to the heat exchanger to which the first and second embodiments are not applied.
Fig. 10 is a cross-sectional view of a fourth embodiment of the integrated heat exchanger tank structure of the present invention. In the case where the air pocket 123 is formed in the partition wall 125 as described above, the leak check path 124 may be formed in the tank 120 and provided in the form of a flow path that allows the air pocket 123 to communicate with the outside. During the process of manufacturing the header tank 100, it is necessary to perform a leakage test by blowing air, and to check whether a portion having a gap is generated during the assembly process, that is, whether there is a problem in that leakage occurs later when the heat exchange medium flows. Typically, leak tests have been performed on the front and rear spaces. That is, in the related art, the leak test must be performed twice. However, in the case where the leak check path 124 is formed as described above, when there is a gap between the partition wall 125 and the manifold 120, air must be discharged to the leak check path 124 along the air pocket 123. Thus, the leak test can be performed simultaneously for the front space and the rear space. That is, since the leak check path 124 is formed, the number of leak test processes can be reduced from two to one, which makes it possible to improve productivity.
The present invention is not limited to the above embodiments, and the scope of the present application is various. Of course, various modifications and embodiments may be made by those skilled in the art to which the invention pertains without departing from the subject matter of the invention as claimed in the claims.
INDUSTRIAL APPLICABILITY
According to the present invention, in the integrated heat exchanger for separately cooling two heat exchange mediums having different temperatures, by having a flow distribution structure in the tank or forming air pockets in the partition wall, there is an effect that thermal stress caused by a temperature difference can be effectively dispersed. Thus, the radiator through which high-temperature cooling water for engine cooling and low-temperature cooling water for electric equipment component cooling, particularly suitable for hybrid vehicles, flows can greatly improve durability and lifetime.

Claims (16)

1. A heat exchanger, the heat exchanger comprising:
a pair of header tanks each having a fluid flow space defined therein by coupling the header and the tank, the pair of header tanks being spaced apart from each other by a predetermined distance and disposed side by side; and
a plurality of tubes, each having two opposite ends fixed to the header tank and configured to define a flow path for a heat exchange medium, the plurality of tubes being arranged in two rows in a forward/rearward direction,
wherein the internal space of the header tank is partitioned by a partition wall into a front heat exchange portion and a rear heat exchange portion,
wherein the heat exchange mediums having different average temperatures flow in the front heat exchange portion and the rear heat exchange portion, respectively, and
wherein the partition wall has thermal stress reducing means.
2. The heat exchanger according to claim 1, wherein the thermal stress reducing means is a flow distribution structure formed on the tank in a region near a partition wall adjacent to the partition wall, the partition wall being a boundary line between the front heat exchange portion and the rear heat exchange portion, and the flow distribution structure is formed such that a flow rate of the heat exchange medium flowing in an inner space of the tube in the region near the partition wall is relatively lower than a flow rate of the heat exchange medium flowing in an inner space of the tube in the remaining region.
3. The heat exchanger according to claim 2, wherein the flow distribution structure is a flow rate adjustment baffle having one end fixed to an inner surface of the tank and the other end disposed to be spaced apart from an inner space of the tube, the flow rate adjustment baffle being formed to reduce a flow rate of the heat exchange medium flowing in the inner space of the tube in a region near the partition wall.
4. The heat exchanger according to claim 2, wherein the flow distribution structure is a flow rate adjustment rib formed as a part of the tank, the flow rate adjustment rib protruding to the inside of the header tank, and an end of the protruding portion being disposed to be spaced apart from the inner space of the tube,
wherein the flow rate regulating rib is formed to reduce a flow rate of the heat exchange medium flowing in the inner space of the tube in the region near the partition wall.
5. The heat exchanger of claim 2, wherein the flow distribution structure is formed in one of the front heat exchange portion and the rear heat exchange portion where the temperature of the heat exchange medium is relatively higher.
6. The heat exchanger according to claim 5, wherein a temperature of the heat exchange medium flowing in the rear heat exchange portion is higher than a temperature of the heat exchange medium flowing in the front heat exchange portion, and the flow distribution structure of the heat exchanger is formed in the rear heat exchange portion.
7. The heat exchanger of claim 2, wherein the flow distribution structure is applied to all locations of the tubes.
8. The heat exchanger of claim 2, wherein the flow distribution structure is formed to be spaced apart only from a position opposite to a position of the tube.
9. The heat exchanger of claim 2, wherein the flow distribution structure is formed to correspond to a range of 10% to 20% of the width of the tube.
10. The heat exchanger of claim 1, wherein the thermal stress reduction means is an air pocket formed in the form of an empty space in the partition wall.
11. The heat exchanger of claim 10, wherein the air pocket extends in an extending direction of the partition wall.
12. The heat exchanger of claim 10, wherein the air pocket is formed to be opened at an end directed toward the header.
13. The heat exchanger of claim 12, wherein an open portion of the air pocket is sealed by a gasket disposed at a portion where the header and the tank are coupled.
14. The heat exchanger of claim 13, wherein the gasket has a sealing protrusion protruding at a position corresponding to the opening portion of the air pocket.
15. The heat exchanger of claim 10, wherein the heat exchanger has a leak check path formed in the tank and provided in the form of a flow path allowing the air pocket to communicate with the outside.
16. The heat exchanger of claim 1, wherein the heat exchanger is a radiator in which a high temperature coolant and a low temperature coolant flow.
CN202180063996.9A 2020-09-18 2021-09-17 Heat exchanger with means for reducing thermal stresses Pending CN116235017A (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
KR10-2020-0120192 2020-09-18
KR20200120192 2020-09-18
KR10-2021-0123159 2021-09-15
KR1020210123159A KR20220037982A (en) 2020-09-18 2021-09-15 Heat exchanger having structure for reducing thermal stress
PCT/KR2021/012794 WO2022060160A1 (en) 2020-09-18 2021-09-17 Heat exchanger having means for reducing thermal stress

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CN (1) CN116235017A (en)
DE (1) DE112021004879T5 (en)
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KR100825709B1 (en) 2001-09-29 2008-04-29 한라공조주식회사 Heat exchanger
KR101344520B1 (en) * 2007-01-12 2013-12-24 한라비스테온공조 주식회사 Heat Exchanger
KR20110134679A (en) * 2010-06-09 2011-12-15 한라공조주식회사 Integrated type heat exchanger
KR101786965B1 (en) * 2010-10-28 2017-11-15 삼성전자주식회사 Header and heat exchanger having the same
BR102013014855B1 (en) * 2013-06-13 2020-12-01 Valeo Sistemas Automotivos Ltda vehicle heat exchanger
KR20180031172A (en) * 2016-09-19 2018-03-28 한온시스템 주식회사 Heat Exchanger for Motor Vehicle

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US20230366630A1 (en) 2023-11-16
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