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(11) | EP 4 462 055 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | A HEAT EXCHANGER |
| (57) A hybrid heat exchanger includes at least one first manifold (10a, 10b) at least
one second manifold (40a, 40b). The first manifold (10a, 10b) s adapted for circulation
of a first fluid within a first set of tubes (20) to define at least a portion of
a first fluid circuit (30). The second manifold (40a, 40b) is adapted for circulation
of a second fluid within a second set of tubes (50) to define at least a portion of
a second fluid circuit (60). At least one second tube (50) comprises a plurality of
micro-channels (52). The second tube (50) is received inside a corresponding first
tube (20) and is in fluid communication with at least one tank (70a, 70b) securely
held within at least one of the first manifold (10a,10b) and the second manifold (40a,
40b) to provide reinforcement thereto.
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TECHNICAL FIELD
[0001] The present invention relates to a heat exchanger. More specifically, the present invention relates to a heat exchanger for a motor vehicle.
BACKGROUND
[0002] Generally, a vehicle may include several heat exchangers for example, a radiator and a gas cooler, a charge air cooler, etc. The gas cooler, for example, is a charge air cooler associated with turbo-charger used in a vehicle. Whereas the radiator is part of a drive-cooling loop that can be at least one of engine cooling loop or battery/ motor cooling loop depending upon whether the vehicle is any one of internal combustion engine driven vehicle hybrid vehicle and electric vehicle. The radiator and gas cooler can be both disposed at front of a vehicle to be impinged by ram air acting as cooling fluid, the operating heat exchange fluids flowing through the radiator and the gas cooler undergo heat exchange with the cooling air flowing there across, as the vehicle traverses. More specifically, coolant flowing through the radiator rejects heat picked up from an engine to the environment, particularly, air flowing across the radiator causing cooling of the coolant. The refrigerant flowing through the gas cooler rejects heat to the outside air, particularly, ram air for causing the phase change of the refrigerant from vapor to liquid state. In case of, for example, electric vehicles, the inlet temperature of the coolant entering the Low temperature radiator is maximum 70 degree Celsius and has coolant flow rate is maximum 1500l/h. The outlet temperature of the coolant egressing the radiator is in the range of 40-60 degree Celsius. The inlet temperature of refrigerant entering the gas-cooler is maximum 140 degree Celsius and the outlet temperature of the refrigerant is 10-15 degree Celsius above temperature of ambient air.
[0003] Generally, the radiator 1 and the gas cooler 2 are disposed overlapping with respect to one other in the direction of the ram air, as illustrated in FIG. 1. Generally, the radiator 1 is disposed downstream of the gas cooler 2 in the direction of ram air. With such arrangement of the radiator 1 and the gas cooler 2, the air reaches the radiator 1 after picking heat rejected by the gas cooler 2 as such the air reaching the radiator 1 is at elevated temperature than the ambient air. More specifically, at higher ambient temperature , for example, 31 degree Celsius, the air temperature downstream of the gas cooler is much higher, thererby posing problem in cooling of the coolant by the radiator. Accordingly, the heat rejecting performance of the radiator 1 is substantially reduced. Inefficient performance of the radiator can have serious implications on the drive cooled by the radiator and in worst circumstances can cause seizure or mechanical failure of drive due to over-heating thereof. Such arrangement, require increasing the dimension of the low temperature radiator, thereby causing packaging issues. Similarly, in case the gas cooler is disposed downstream of the radiator in the direction of ram air, the air reaches the gas cooler after picking heat rejected by the radiator and the air reaching the gas cooler is at elevated temperature than the ambient air. Accordingly, the efficiency and performance of the gas cooler is substantially reduced.
[0004] In case the gas cooler is a water-cooled, the coolant, i.e. water is received from the radiator after the coolant had extracted heat from the radiator. Accordingly, the coolant received in the gas cooler is incapable of cooling the refrigerant. Accordingly, the efficiency and performance of the gas cooler is reduced. None of the prior art heat exchangers that function as multiple heat exchangers with at least one heat exchanger being gas cooler defining first and second passes.
[0005] Further, the radiator and the gas cooler are required to be disposed sufficiently spaced apart to achieve sufficient and proper air-flow there across. Such an overlapping arrangement of the radiator and the gas-cooler occupies more space thereby resulting in packaging issues.
[0006] Accordingly, there is a need for a heat exchanger called, for example, a hybrid heat exchanger that combines functions of two heat exchangers in one heat exchanger, thereby addressing the packaging issues, reduces overall weight and the vehicle on which such heat exchanger is mounted exhibits improved performance. It should be noted that the terms hybrid heat exchanger and heat exchanger may be used interchangeably. Also, there is a need for a heat exchanger that combines function of two or more heat exchanger in one, wherein at least one of the heat exchanger is a gas cooler. Further, there is a need for a hybrid heat exchanger that obviates the disadvantages caused by overlapping configuration of the radiator and gas cooler. More specifically, there is a need for a hybrid heat exchanger that prevents the problems arising due to obstructed air flow to one of radiator and gas-cooler by the other, packaging issues and the downstream radiator or gas-cooler receiving air at elevated temperature due to air being pre-heated by the other radiator or gas-cooler disposed upstream thereof. Further, conventional known refrigerants flowing through the compressor such as for example, 1234yf is harmful to the environment and facing sanctions. The natural refrigerants, such as CO2 known as R744 or propane known as R290 and alike seem to be environmentally friendly option, however, these are high pressure refrigerants and the conventional heat exchangers fail to withstand the high pressure. Accordingly, there is a need for hybrid heat exchangers that can withstand the high-pressure refrigerant.
[0007] An object of the present invention is to provide a heat exchanger that combines functions of two heat exchangers in one heat exchanger, thereby addressing packaging issues and reliability issues.
[0008] Yet another object of the present invention is to provide a heat exchanger that prevents problems of reduced efficiency and performance of one of the heat exchanger due to obstructed air-flow there through faced in conventional heat exchangers.
[0009] Still another object of the present invention is to provide a heat exchanger that functions as multiple heat exchangers with at least one heat exchanger being gas-cooler.
[0010] Another object of the present invention is to provide hybrid heat exchanger that are compatible to handle high pressure refrigerant by with standing high pressures exerted by the high pressure refrigerants.
[0011] In the present description, some elements or parameters may be indexed, such as a first element and a second element. In this case, unless stated otherwise, this indexation is only meant to differentiate and name elements which are similar but not identical. No idea of priority should be inferred from such indexation, as these terms may be switched without betraying the invention. Additionally, this indexation does not imply any order in mounting or use of the elements of the invention.
SUMMARY
[0012] A hybrid heat exchange for a motor vehicle is disclosed in accordance with an embodiment of the present invention. The hybrid heat exchanger includes at least one first manifold and at least one second manifold. The at least one first manifold is adapted for circulation of a first fluid within a first set of tubes, the first set of tubes being configured define at least a portion of a first fluid circuit. The at least one second manifold is adapted for circulation of a second fluid within a second set of tubes, the second set of tubes being configured to define at least a portion of a second fluid circuit. The at least one second tube comprises a plurality of micro-channels, wherein the second tube is received inside a corresponding first tube and is in fluid communication with at least one tank that is securely held within at least one of the first manifold and the second manifold to provide reinforcement thereto. The at least one second tube with the micro-channels define fluid flow passage for the second fluid and annular space between the first tube and the second tube defines fluid flow passage for the first fluid.
[0013] Generally, the at least one tank comprises at least one of an inlet port and outlet port for ingress and egress of the second fluid with respect to the at least one tank.
[0014] Preferably, the at least one tank comprises at least one reinforcement and distribution wall dividing interior of the at least one tank into a first chamber and a second chamber.
[0015] Particularly, the at least one tank comprises a plurality of slots arranged along and between longitudinal walls thereof and extending orthogonal to the longitudinal walls thereof.
[0016] Further, the hybrid heat exchanger comprising at least one baffle disposed between and separating interior of co-axially arranged adjacent tanks with respect to each other.
[0017] Generally, the second tube is adapted for circulation of high-pressure refrigerant there through and is co-axially arranged within the corresponding first tube.
[0018] Particularly, the second tube is longer than the corresponding first tube, passes through the first manifold and is in fluid communication with the tank securely held within the second manifold disposed after the first manifold.
[0019] Generally, the first tube and the second tube comprises at least one of ribs and protrusions respectively formed thereon.
[0020] Particularly, the first tube comprises dimples formed on opposite sides thereof that protrudes inwardly into interior of the first tube for securely holding the corresponding second tube inside the first tube.
[0021] Specifically, the first manifold and the second manifold are formed by assembling at least one of first header, a second header, a cover and corresponding end caps.
[0022] Further, the first header comprises support elements inwardly extending there from and adapted to support the second header thereon.
[0023] Furthermore, at least one of the first header and the cover comprises respective crimping tabs and adapted to form crimping connection between the first header and the corresponding cover.
[0024] Particularly, the first header comprises first apertures adapted to receive the first tubes that configure fluid communication between the spaced apart first manifolds.
[0026] Further, the second header comprises second apertures formed thereon and adapted to receive the second tubes that configure fluid communication between the corresponding spaced apart second manifolds.
[0027] Particularly, the second apertures are aligned with respect to either at least one slot formed on the closed end of the respective tanks or the open end of the respective tanks.
[0028] Specifically, at least one of the first header and the corresponding cover are assembled to each other with the corresponding second header received in either one of the first header and the cover to define the first manifold and the corresponding second manifold.
[0029] More specifically, the second header is received in the open end of the corresponding first header, the first header and the second header is received in a first opening of the corresponding cover to define the first manifold and the second manifold.
[0030] Generally, the hybrid heat exchanger comprises a first inlet, a first outlet, a second inlet and a second outlet. The first inlet and the first outlet are configured either on the same first manifold or on different first manifolds of the first manifolds. The second inlet and second outlet are configured on the same second manifold but reverse to the first inlet and first outlet and adapted to configure U-flow of the second fluid through the second set of tubes. Such configuration of the first inlet and the first outlet and the second inlet and second outlet configures counter flow between first fluid flowing through the first tubes and second fluid flowing through the second tubes. Some tubes of the second tubes define a first gas-cooling pass while the remaining tubes of the second tubes define a second gas-cooling pass, the second gas-cooling pass acting as sub-cooler, in case the ambient temperature is below 31 degree Celsius.
[0031] Particularly, the first gas-cooling pass is in fluid communication with the second gas-pass via the second manifold opposite to the second manifold of the second manifolds on which the second inlet and second outlet are formed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Other characteristics, details and advantages of the invention can be inferred from the description of the invention hereunder. A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying figures, wherein:
FIG. 1 illustrates a conventional arrangement of a first heat exchanger and a second heat exchanger arranged in overlapping manner with respect to each other;
FIG. 2 illustrates a front view of a hybrid heat exchanger in accordance with an embodiment of the present invention;
FIG. 3 illustrates an enlarged view depicting one side of the hybrid heat exchanger, particularly, crimping connection between a cover and a first header defining a first and a second manifold with a second manifold with a second header;
FIG. 4 illustrates an exploded view of the hybrid heat exchanger at one side thereof;
FIG. 5a illustrates a side view of one side of the hybrid heat exchanger of FIG. 2 depicting internal details of the first manifold and the second manifold receiving a tank in accordance with an embodiment of the present invention;
FIG. 5b illustrates a sectional view depicting internal details of the first manifold and the second manifold of FIG. 5a in fluid communication with first tube and corresponding second tube respectively;
FIG. 6a illustrates a side view depicting internal details of the first manifold and the second manifold receiving an open ended tank in accordance with another embodiment of the present invention;
FIG. 6a illustrates a section view depicting internal details of the first manifold and the second manifold of FIG. 6a;
Fig. 7 illustrates an isometric view of a tank of the hybrid heat exchanger of FIG. 2 depicting a reinforcement and distribution wall formed therein;
Fig. 8 illustrates another isometric view of the tank of FIG. 7 depicting slots formed on underside thereof;
FIG. 9 illustrates a tube in tube configuration used for heat exchange in the hybrid heat exchanger of FIG. 2, wherein a second tube that includes a plurality of micro-channels is received and held inside a first tube;
FIG. 10 illustrates an isometric view of the second manifold without a tank and a cover for depicting internal details thereof;
FIG. 11 illustrates an isometric view of the first manifold without a second header for depicting internal details thereof;
FIG. 12 illustrates an isometric view of a first tube of a first set of tubes with dimples formed thereon, also are depicted enlarged views of the end portions of the first tube;
FIG. 13 illustrates an isometric sectional view of the first tube of FIG. 12 depicting internal details thereof, also is depicted an enlarged view depicting the dimple protruding into interior of the first tube;
FIG. 14 illustrates an isometric view depicting tube in tube arrangement of the first tube of FIG. 12 and a second tube received and held within the first tube;
FIG. 15 - FIG. 20 illustrate different configurations of the heat exchanger with different positioning of the first inlet and first outlet for coolant and second inlet and second outlet for refrigerant; and
FIG. 21 illustrates a side view of one side of the heat exchanger in accordance with another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0033] It must be noted that the figures disclose the invention in a detailed enough way to be implemented, said figures helping to better define the invention if needs be. The invention should however not be limited to the embodiment disclosed in the description.
[0034] Although, the present invention is explained in the forthcoming description and the accompanying drawings with an example of heat exchanger for a motor vehicle, particular a heat exchanger that that combines functions of two heat exchangers in one heat exchanger. More specifically, the hybrid heat exchanger of present invention combines functions of a radiator and a gas-cooler for a vehicle, thereby eliminating the need for multiple heat exchangers and problems associated with multiple heat exchangers arranged in overlapping configuration, for example packaging issues and performance and efficiency issues. Also, the hybrid heat exchanger of the present invention utilizes a tank received inside a second manifold for reinforcement thereof for circulation of high pressure refrigerant through the hybrid heat exchanger. However, the present invention is applicable for any hybrid heat exchanger for use in vehicular and non-vehicular environment where it is required to combine functions of two heat exchangers into one to address packaging issues, and other problems faced with overlapping arrangement of multiple heat exchangers and permit circulation of high-pressure refrigerant through the hybrid heat exchanger.
[0035] FIG. 2 of the accompanying drawings illustrates a front view of a hybrid heat exchanger 100 in accordance with an embodiment of the present invention for a motor vehicle. FIG. 3 illustrates an enlarged view depicting one side of the hybrid heat exchanger 100. FIG. 4 illustrates an exploded view of one side of the hybrid heat exchanger 100. The heat exchanger 100 includes at least one first manifold 10a, 10b and at least one second manifold 40a, 40b.
[0036] At least one first manifold 10a, 10b is for circulation of a first fluid within a first set of tubes 20, wherein the first set of tubes 20 define at least a portion of a first fluid circuit 30. In accordance with an embodiment of the present invention, the first fluid circuit 30 is an engine cooling circuit for coolant flow with a radiator 32 being part of the first fluid circuit 30. In accordance with an embodiment, the heat exchanger 100 includes a pair of first manifolds 10a and 10b, particularly, a first distribution manifold 10a and a first collection manifold 10b to configure I -flow of the coolant. In such configuration, the first distribution manifold 10a distributes heated coolant from the first fluid circuit, particularly, the engine cooling circuit, to the first set of tubes 20. The first collection manifold 10b collects coolant from the first set of tubes 20 after the heated coolant had absorbed heat from the refrigerant flowing through micro-channels 52 of corresponding second tubes 50 received in the first tubes 20. The air flowing across the first tubes 20 cools the heated coolant. In accordance with another embodiment of the present invention as illustrated in FIG. 2, although, the heat exchanger 100 includes two first manifolds 10a and 10b, however, one of the two first manifolds 10a and 10b, for example, 10a is divided into a distribution section and a collecting section by an internal baffle. In such configuration, a first inlet 16a for ingress of the coolant and the a first outlet 16b for egress of the coolant are formed on the first manifold 10a, particularly, on the distribution section and the collection section of the first manifold 10a to configure U-flow of the coolant in the first set of tubes 20. Although, in the accompanying drawings the first inlet 16a and the first outlet 16b are depicted on sides of the first manifold 10a, 10b, however, the same can be on the top side along with the second inlet 46a and the second out let 46b. Particularly, the distribution section distributes coolant to few first tubes 20 configuring a first coolant pass and the collecting section collects coolant from the remaining first tubes configuring a coolant return pass. More specifically, the other of the two first manifolds 10a and 10b, the first manifold 10b in this case, configures fluid communication between the coolant first pass and the coolant return pass. The flow of the coolant through the first manifolds 10a and 10b and the first tubes 20 is depicted by line arrows A in the FIG. 2. Further, the heat exchanger 100 configured with a single first manifold 10a, 10b divided into separate sections by a baffle disposed inside the single first manifold 10a, 10b, wherein, the separate sections of the single first manifold 10a, 10b are connected by U-tubes is also within the scope of the present invention. In such configuration, the first section of the single first manifold 10a, 10b distributes the coolant to one end of the U-tubes and the second section of the single manifold 10a, 10b collects the coolant from the other end of the U-tubes. However, for sake of brevity of the present document, such configuration of single first manifold 10a,10b is not described in details.
[0037] At least one second manifold 40a, 40b is configured for circulation of a second fluid, particularly, high pressure refrigerant, for example, R744, R290, or the mixture of the two, within the second set of tubes 50 to define at least a portion of a second fluid circuit 60. In accordance with an embodiment of the present invention, the second fluid circuit 60 is an air conditioning loop for refrigerant flow with a gas-cooler 62 being part of the second fluid circuit 60. Similar to the first manifold 10a, 10b, the heat exchanger 100 may comprise a pair of second manifolds 40a and 40b, particularly, a second distribution manifold 40a and a second collection manifold 40b to configure I-flow of refrigerant. In one embodiment, the first distribution manifold 40a distributes refrigerant from the second fluid circuit, particularly, an air-conditioning loop, to the second set of tubes 50, particularly, the micro-channels 52 of the second tubes 50. The second collection manifold 40b collects refrigerant from the second set of tubes 50 after the refrigerant had rejected heat to the coolant flowing in annular space between first tubes 20 and the second tubes 50 received in the first tubes 20. The heat exchanger 100 may include the pair of second manifolds 40a and 40b, however, one of the second manifolds 40a and 40b, for example, 40a may be divided into a distribution section and a collecting section by an internal baffle. In such configuration a second inlet 46a for ingress of the refrigerant and a second outlet 46b for egress of the refrigerant are formed on the second manifold 40a, particularly, on the distribution section and the collection section of the second manifold 40a to configure U-flow of the refrigerant in the second set of tubes 50. The position of the second inlet 46a and the second outlet 46b on the second manifold 40a is reversed with respect to the position of the first inlet 16a and the first outlet 16b on the first manifold 10a to configure counter flow between the coolant flowing through the first tubes 20 and the refrigerant flowing through the second tubes 50. The distribution section distributes refrigerant into few of the second tubes 50 configuring a first refrigerant pass and the collecting section collects refrigerant from the remaining second tubes to configuring a refrigerant return pass. More specifically, the other of the second manifolds 40a and 40b, particularly, the second manifold 40b in this case, configures fluid communication between the refrigerant first pass and the refrigerant second pass or return pass. The flow of the refrigerant through the second manifolds 40a and 40b and the second tubes 50 is depicted by solid arrows B in the FIG. 2.
[0038] The refrigerant circulating through the hybrid heat exchanger may be a high pressure refrigerant such as for example R744 and propane as these are comparatively environment friendly than the conventional refrigerants such as for example 1234yf that is harmful to the environment and facing sanctions. However, the heat exchanger is also suitable for circulating conventional refrigerants within, if needed. As the refrigerant circulating through the hybrid heat exchanger, particularly, circulating through the second tubes 50 and the second manifolds 40a and 40b is a high pressure refrigerant, the second tubes 50 and the second manifolds 40a and 40b are required to be protected against damage from the high pressure refrigerant circulating there through.
[0039] To make the second tubes 50 and the second manifolds 40a and 40b compatible to the high-pressure refrigerant flow, the second tubes 50 are formed by extrusion and the second manifolds 40a and 40b are reinforced by corresponding tanks 70a and 70b. The micro-channel are oval shaped and the dimension of the micro-channels is also reduced and wall thickness of the micro-channel tubes 50 is increased to help the second tubes to withstand high-pressure refrigerant flow there through.
[0040] Referring to the side view and the sectional view of one side of the hybrid heat exchanger 100 depicted in FIG. 5a and FIG. 5b respectively, a tank 70a, 70b securely held inside the second manifold 40a, 40b to reinforce the structure of the components assembled to define the second manifold 40a, 40b. Generally, the second tube 50 received inside a corresponding first tube 20 is in fluid communication with at least one tank 70a, 70b that is securely held within at least one of the first manifold 10a, 10b and the second manifold 40a, 40b to provide reinforcement thereto to withstand the high pressure of the high-pressure refrigerant. Particularly, the second tube 50 is in fluid communication with the tank 70a, 70b securely held with the corresponding second manifold 40a, 40b. The at least one second tube 50 with the micro-channels 52 define fluid flow passage for the second fluid, particularly, high-pressure refrigerant and annular space between the first tube 20 and the second tube 50 defines fluid flow passage for the first fluid.
[0041] Referring to the FIG. 7 and FIG.8, the first and second isometric views of at least one tank 70a, 70b is depicted. Generally, the at least one tank 70a, 70b comprises at least one of an inlet port 72a, 72b and an outlet port 71a, 71b for ingress and egress of the second fluid with respect to the at least one tank 70a, 70b. The inlet port 72a and the outlet port 73a formed on the corresponding separate, adjacent, co-axial tanks 70a are aligned with respect to the second inlet 46a and the second outlet 46b respectively formed on same manifold 40a, 40b, particularly, same cover 44a, 44b to configure u-flow of the refrigerant. Preferably, the at least one tank 70a, 70b comprises at least one reinforcement and distribution wall 74a, 74b dividing interior of the at least one tank 70a, 70b into a first chamber 73a, 73b and a second chamber 75a, 75b. Particularly, the at least one tank 70a, 70b comprises a plurality of slots 76a, 76b arranged along and between longitudinal walls thereof and extending orthogonal to the longitudinal walls thereof. Further, the hybrid heat exchanger 100 comprises at least one baffle 78 disposed between and separating interior of co-axially arranged adjacent tanks with respect to each other creating fluid isolation between the interior of co-axially arranged adjacent tanks.
[0042] Referring to the FIG. 5a, the first manifold 10a, 10b and the second manifold 40a, 40b are formed by assembling a first header 12a, 12b, a second header 22a, 22a, a cover 44a, 44b and the end caps 47a, 47b. The first header 12a, 12b, the second header 22a, 22b and the cover 44a, 44b are assembled and joined together by using any of the joining processes, such as for example, brazing. However, the present invention is not limited to any particular joining process for forming secure connection between the components and is not limited to brazing. The first header 12a, 12b includes first apertures 12c, 12d formed thereon to receive the first tubes 20 that configure fluid communication between the spaced apart first manifolds 10a and 10b. Extreme ends of the first tubes 20 are securely held within respective first apertures 12c and 12d formed on the respective first header 12a and 12b and are joined thereto by any of the joining process such as for example, brazing. The present invention is not limited to any particular joining process for configuring secure connection between the extreme ends of the first tubes 20 and the first header 12a and 12b and is not limited to brazing. Such configuration prevents any leakage of the first fluid, particularly, coolant from first manifold 10a, 10b through the gap between extreme ends of the first tubes 20 and corresponding first apertures 12c, 12d formed on the first header 12a, 12b. The second header 22a, 22b includes second apertures 22c, 22d formed thereon to receive the second tubes 50 that configures fluid communication between the spaced apart second manifolds 40a and 40b. The extreme ends of the second tubes 50 are securely held within respective second apertures 22c and 22d formed on the respective second header 22a and 22b and are joined thereto by any of the joining process such as for example, brazing. The second apertures 22c, 22d are aligned with respect to at least one slot 76a, 76b formed on the respective tanks 70a, 70b to configure fluid communication between the tank 70a, 70b and the second tubes 20 received in the second apertures 22c, 22d. The second apertures 22c, 22d are either aligned with respect to the first apertures 12c, 12d formed on closed end of the respective tank 70a, 70b or the open end of the respective tank 70, 70b.
[0043] In accordance with another embodiment of the present invention, the tank 70a, 70b are open ended as illustrated in FIG. 6a and FIG. 6b instead of the tank 70a, 70b being closed ended with slots 76a, 76b as illustrated in FIG. 5a and FIG. 5b. In such configuration the second apertures 22c, 22d are aligned with respect to open ends of the respective tanks 70a, 70b to configure fluid communication between the tank 70a, 70b and the second tubes 50 received in the second apertures 22c, 22d. Again, the present invention is not limited to any particular joining process for configuring secure connection between the extreme ends of the second tubes 50 and the second header 22a and 22b and is not limited to brazing. Such configuration prevents any leakage between the first manifold 10a, 10b and the respective second manifold 40a, 40b through the gap between extreme ends of the second tubes 50 and the respective second apertures 22c, 22d. The first header 12a, 12b and the cover 44a, 44b are assembled to each other with the corresponding second header 22a, 22b received in either one of the first header 12a, 12b and the cover 44a, 44b to define the first manifold 10a, 10b and the corresponding second manifold 40a, 40b. More specifically, at least one of the first header 12a, 12b and the corresponding cover 44a, 44b comprises respective crimping tabs 13a, 13b and 45a, 45b adapted to form crimping connection between the first header 12a, 12b and the corresponding cover 44a, 44b with the tank 70a, 70b and second header 22a, 22b held there-between. Particularly, the first header 12a, 12b comprises support elements 14a, 14b inwardly extending there from and adapted to support the second header 22a, 22b thereon as the first header 12a, 12b is being crimped to the cover 44a, 44b with the tank 70a, 70b and the second header 22a, 22b held there-between.
[0044] In accordance with an embodiment illustrated in FIG. 6a and FIG. 6b, the tank 70a, 70b is supported on a corresponding reinforcement plate 80a, 80b that is disposed between the tank 70a, 70b and the second header 22a, 22b. The reinforcement plate 80a, 80b further includes slots aligned with the second apertures 22c, 22d for fluid communication between interior of the tank 70a, 70b and the second tubes 50 received in the second apertures 22c, 22d.
[0045] Again referring to the FIG. 5a, the cover 44a, 44b is in the form of an enclosure with a stepped configuration that includes a first portion with first opening and second portion with a second opening. The first opening is wider than the second opening to form an intermediate neck portion at the interface between the first portion and the second portion of the cover 44a, 44b. The cover 44a, 44b at least partially encapsulates the corresponding tank 70a, 70b as the cover 44a, 44b is crimped to the first header 12a, 12b. In accordance with a specific embodiment as illustrated in FIG. 21, the cover 44a, 44b is open ended from both sides. Particularly, the cover 44a, 44b includes an open end and a cutout 49a, 49b opposite to the open end, the tank abuts against periphery of the cutout 49a, 49b to prevent further advance of the tank 70a, 70b into the cover 44a, 44b. Particularly, the open end of the cover 44a, 44b receives the tank 70a. 70b and the assembly of the first header 12a, 12b and the second header 22a, 22b from the open end, whereas the periphery of the cutout limits further insertion of the tank 70a, 70b and the assembly of the first header 12a, 12b and the second header 22a, 22b inside the cover 44a, 44b. Such configuration of the cover 44a, 44b acts as stress relieving feature by adapting according to the tank 70a, 70b.
[0046] The first header 12a, 12b may be also in the form of an enclosure having a closed end and an open end. The second header 22a, 22b is received in the open end of the first header 12a, 12b. The first header 12a, 12b with the second header 22a, 22b received therein is received in the first opening of the corresponding cover 44a, 44b. The neck portion 48a, 48b formed on the cover 44a, 44b prevents further advance of the first header 12a, 12b along with the second header 22a, 22b within the cover 44a, 44b to define the first manifold 10a, 10b and the second manifold 40a, 40b. More specifically, the second header 22a, 22b separates the first manifold 10a, 10b with respect to the second manifold 40a, 40b. Alternatively, the second header 22a, 22b is received in the first opening of the corresponding cover 44a, 44b and thereafter, the first header 12a, 12b is received in the first opening of the corresponding cover 44a, 44b to define the first manifold 10a, 10b and the second manifold 40a, 40b. However, the present invention is not limited to any particular configuration and sequence of connections between the first header 12a, 12b, the second header 22a, 22b and the cover 44a, 44b to form the first manifold 10a, 10b and the second manifold 40a, 40b.
[0047] At least one second tube 50 includes plurality of micro-channels 52 formed by extrusion. The micro-channels 52 can have square or triangular cross section. Preferably, the micro-channels 52 are having oblong cross section. However, the present invention is not limited to any particular cross section of the micro-channels 52 or method of forming the micro-channels 52. At least one of the second tubes 50 may be received inside the first tube 20. Referring to the FIG. 5a and FIG. 5b, the second tube 50 is comparatively longer than the corresponding first tube 20, so that it extends out of the first tube 20. The second tube 50 passes through the first manifold 10a, 10b, it extends out of the second header 22a, 22b and it is in fluid communication with the tank 70a, 70b securely held in the corresponding second manifold 40a, 40b disposed after the corresponding first manifold 10, 10b. In a preferred embodiment, one second tube 50 is received in one first tube 20 as illustrated in FIG. 9 - FIG. 11. Further, the second tube 50 is co-axially arranged within the corresponding first tube 20. Generally, first tube 20 and the second tube 50 include ribs/dimples 20a and protrusions 54 respectively formed thereon for securely holding the second tube 50 inside the first tube 20. In accordance with an embodiment of the present invention, the first tube 20 is formed by folding. In accordance with another embodiment as illustrated in FIG. 9, the first tube 20 includes dimples 20a formed on opposite sides thereof. The dimples 20a protrude inwardly into interior of the first tube 20 to interact with opposite sides of the corresponding second tube 50 to securely hold the corresponding second tube 50 inside the first tube 20. The folded ends of the first tube 20 inwardly extend into the interior of the first tube 20 to interact with the second tube 50 received in the first tube 20 for positioning of the second tube 50 inside the first tube 20. Particularly, the folded ends of the first tube 20 and the dimples 20a together arrest the movement of the second tube 50 in the X- direction. Other dimples 20a formed on the lateral sides of the first tube 20 arrest the movement of the second tube 50 in the Y- direction. The dimples 20a formed on opposite sides of the first tube 20 are of same size to coaxially hold the second tube 50 within the first tube 20. Alternatively, the dimples 20a formed on opposite sides of the first tube 20 are of different dimensions to eccentrically hold the second tube 50 within the first tube 20. The dimples 20a formed on opposite sides of the tube 20 are off set from opposite dimples. The second tube 50 may further include outwardly extending protrusions 54 protruding from opposite sides thereof to enable placement and holding of the second tube 50 inside the first tube 20. The outwardly extending protrusions 54 is formed during extrusion of the channels 52. In accordance with another embodiment, the dimples are partially formed on the first tube 20 and partially formed on the second tube 50 to interact with each other for securely holding the second tubes 50 within the corresponding first tubes 20. However, the present invention is not limited to any particular configuration, number, and placement of the dimples 20a or protrusions 54 formed on the first tube 20 and the second tube 50 respectively, as far as the dimples 20a or protrusions 54 facilitate secure holding of the second tube 50 inside the first tube 20.
[0048] In such "tube in tube" configuration, wherein the second tube 50 received in the first tube 20, the micro-channels 52 may define fluid flow passages for the second fluid, for example the refrigerant and the annular space between the first tube 20 and the second tube 50 may define fluid flow passage for the first fluid, for example, the coolant. Further, the channels 52 of the second tubes define the flow passages for the second fluid, for example, the high-pressure refrigerant. In accordance with an embodiment of the present invention, at least one of the first fluid and the second fluid is a coolant. Instead of single second tube 50 being held in the first tube 20, multiple second tubes 50 are received and held in one first tube 20. In such case, the multiple second tubes 50 are connected and inserted within the first tube 20. The inwardly extending dimples 20a formed on the first tube interact with the opposite sides of the extreme second tubes 50 held in the first tube 20 and adjacent to the walls of the first tube 20 to hold the second tubes 50 within the first tube 20.
[0049] The flow of the coolant and the refrigerant through the first set of tubes 20 and the second set of tubes 50 can be either parallel flow or counter flow based on the positioning of the first inlet 16a and the first outlet 16b for the coolant, a second inlet 46a and a second out let 46b for the refrigerant. FIG. 15 - FIG. 20 illustrate different configurations of the heat exchanger based on different combinations of the positioning of the first inlet 16a and the first outlet 16b for coolant, the second inlet 46a and the second outlet 46b for refrigerant. However, the heat exchanger of the present invention is not limited to any particular configurations depicted, can have any configuration, with different combinations of refrigerant and coolant flows based on position of the first inlet 16a, the first outlet 16b, the second inlet 46a and the second outlet 46b.
[0050] Generally, the first inlet 16a and the first outlet 16b are configured either on the same first manifold 10a, 10b or on different first manifolds 10a and 10b of the first manifolds 10a and 10b. In accordance with an embodiment as illustrated in FIG. 15, 16, 18-20, the first inlet 16a and the first outlet 16b are formed one of the first manifold 10a. In accordance with another embodiment of the present invention as illustrated in FIG. 17, the first inlet 16a and the first outlet 16b are formed on different first manifolds 10a and 10b disposed opposite to one another. The coolant inlet 16a formed on side opposite to the side on which the refrigerant inlet 46a is formed.
[0051] Further, the second inlet 46a and the second outlet 46b are configured on the same second manifold 40a, 40b to configure U-flow of the second fluid through the second set of tubes 50. Furthermore, such configuration of the first inlet 16a and the first outlet 16b formed revered to the second inlet and outlet 46a and 46b configures counter flow between first fluid flowing through the first tubes 20 and second fluid flowing through the second tubes 50. In accordance with an embodiment, some tubes 50a of the second tubes 50 define a first pass while the remaining tubes 50b of the second tubes 50 define a second pass that is return pass. Generally, the first pass includes more number of second tubes 50 than the second heat exchange tubes in the second pass. The first pass is in fluid communication with the second pass via the second collecting manifold 40b.
[0052] The heat exchanger 100 can be incorporated in any cooling loop configured in a vehicle, wherein the heat exchanger functioning as radiator 32 supplies coolant to any of the vehicle heat exchangers to extract heat from any of the heat-generating component in the vehicle. Specifically, the vehicle heat exchangers can be any one of radiator, water charged air cooler, chiller and the heat-generating means can be any one of engine, e-motor and battery in a vehicle that is either one of internal-combustion engine driven, electric motor driven or any hybrid vehicle.
1. A hybrid heat exchanger (100) for a motor vehicle comprising:
• at least one first manifold (10a,10b) adapted for circulation of a first fluid within a first set of tubes (20), the first set of tube (20) being configured to define at least a portion of a first fluid circuit (30);
• at least one second manifold (40a, 40b) adapted for circulation of a second fluid within a second set of tubes (50), the second set of tubes (50) being configured to define at least a portion of a second fluid circuit (60),
characterized in that at least one second tube (50) comprises a plurality of micro-channels (52), wherein the second tube (50) is received inside a corresponding first tube (20) and is in fluid communication with at least one tank (70a, 70b) securely held within at least one of the first manifold (10a,10b) and the second manifold (40a, 40b) to provide reinforcement thereto, and in that
at least one second tube (50) with the micro-channels (52) defines fluid flow passage for the second fluid and annular space between the first tube (20) and the second tube (50) defines fluid flow passage for the first fluid.
2. The hybrid heat exchanger (100) as claimed in the previous claim, wherein the at least
one tank (70a, 70b) comprising at least one of an inlet port (72a, 72b) and outlet
port (71a, 71b) for ingress and egress of the second fluid with respect to the at
least one tank (70a, 70b).
3. The hybrid heat exchanger (100) as claimed in any of the preceding claims, wherein
the at least one tank (70a, 70b) comprising at least one reinforcement and distribution
wall (74a, 74b) dividing interior of the at least one tank (70a, 70b) into a first
chamber (73a, 73b) and a second chamber (75a, 75b).
4. The hybrid heat exchanger (100) as claimed in any of the preceding claims, wherein
the at least one tank (70a, 70b) comprising a plurality of slots (76a, 76b) arranged
along and between longitudinal walls thereof and extending orthogonal to the longitudinal
walls thereof.
5. The hybrid heat exchanger (100) as claimed in any of the preceding claims further
comprising at least one baffle (78) disposed between and separating interior of co-axially
arranged adjacent tanks (70a, 70b) with respect to each other.
6. The hybrid heat exchanger (100) as claimed in in any of the preceding claims, wherein
the second tube (50) is adapted for circulation of high-pressure refrigerant there
through and is co-axially arranged within the corresponding first tube (20).
7. The hybrid heat exchanger (100) as claimed in any of the preceding claims, wherein
the second tube (50) is longer than the corresponding first tube (20), passes through
the first manifold (10a, 10b) and is in fluid communication with the tank (70a, 70b)
securely held within the second manifold (40a, 40b) disposed after the first manifold
(10a, 10b).
8. The hybrid heat exchanger (100) as claimed in any of the preceding claims, wherein
the first manifold (10a, 10b) and the second manifold (40a, 40b) are formed by assembling
least one of a first header (12a, 12b), a second header (22a, 22b), a cover (44a,
44b) and corresponding end caps (47a, 47b).
9. The hybrid heat exchanger (100) as claimed in the claim 8, wherein the first header
(12a, 12b) comprises support elements (14a, 14b) inwardly extending there from and
adapted to support the second header (22a, 22b) thereon.
10. The hybrid heat exchanger (100) as claimed in claim 8, wherein at least one of the
first header (12a, 12b) and the cover (44a, 44b) comprises respective crimping tabs
(13a, 13b) and (45a, 45b) adapted to form crimping connection between the first header
(12a, 12b) and the cover (44a, 44b).
11. The hybrid heat exchanger (100) as claimed in claim 8, wherein the first header (12a,
12b) comprises first apertures (12c, 12d) adapted to receive the first tubes (20)
that configure fluid communication between the spaced apart first manifolds (10a)
and (10b).
12. The hybrid heat exchanger (100) as claimed in the claim 8, wherein the cover (44a,
44b) at least partially encapsulates the tank (70a, 70b).
13. The hybrid heat exchanger (100) as claimed in claim 8, wherein the second header (22a,
22b) comprises second apertures (22c, 22d) formed thereon and adapted to receive the
second tubes (50) that configure fluid communication between the corresponding spaced
apart second manifolds (40a) and (40b).
14. The hybrid heat exchanger (100) as claimed in the previous claim, wherein the second
apertures (22c, 22d) are aligned with respect to at least one slot (76a, 76b) formed
on closed end of the respective tanks (70a, 70b) or the open end of the respective
tanks (70a, 70b).
15. The hybrid heat exchanger (100) as claimed in the claim 8, wherein at least one of
the first header (12a, 12b) and the corresponding cover (44a, 44b) are assembled to
each other with the corresponding second header (22a, 22b) received in either one
of the first header (12a, 12b) and the cover (44a, 44b) to define the first manifold
(10a,10b) and the corresponding second manifold (40a, 40b).
16. The hybrid heat exchanger (100) as claimed claim 8, wherein the second header (22a,
22b) is received in the open end of the corresponding first header (12a, 12b) and
the first header (12a, 12b) along with the second header is received in a first opening
of the corresponding cover (44a, 44b) to define the first manifold (10a, 10b) and
the second manifold (40, 40b).