A heat exchanger core

Abstract

The subject- matter of the invention is a heat exchanger core (100) comprising : a plurality of primary plates (10), and a plurality of secondary plates (20), disposed alternately with respect to each other to define a height (Z) of the heat exchanger core (100), wherein, the primary plates (10) and the secondary plates (20) define plurality of first fluid flow passages (30) configured to allow at least a first fluid to flow therein, wherein, the plurality of primary plates (10) comprise: at least a plurality of first primary plates (10a) each comprising at least a first aperture (12a) and a second aperture (14a) allowing the first fluid to pass therethrough, at least a plurality of second primary plates (10b) each comprising at least a first hole (12b) and at least a second hole (14b) allowing the first fluid to pass therethrough, at least one third primary plate (10c) each comprising at least a second opening (14c) allowing the first fluid to pass therethrough, wherein the of secondary plates (20) comprise: at least a plurality of first secondary plates (20a) comprising at least a first orifice (22a) and a second orifice (24a) allowing the first fluid to pass therethrough, at least a plurality of second secondary plates (20b) comprising at least a first perforation (22b) and at least a second perforation (24b) allowing the first fluid to pass therethrough, wherein one or more of the first apertures (12a), one or more of the first holes (12b), one or more of the first orifices (22a) and one or more of the first perforation (22b) are aligned with respect to each other along the height (Z) of the heat exchanger core (100) to form a first channel (40), wherein one or more of the second apertures (14a), one or more of the second holes (14b), one or more of the second openings (14c), one or more of the second orifices (24a) and one or more of the second perforations (24b) are aligned with respect to each other along the height (Z) of the heat exchanger core (100) to form a second channel (50), characterised in that, each second primary plate (10b) further comprises a third hole (16b), each third primary plate (10c) further comprises a third opening (16c) and each second secondary plate (20b) further comprises a third perforation (26b), wherein one or more of the third holes (16b) one or more of second primary plates (10b), at least one third opening (16c) of the at least one third primary plate (10c) and one or more of the third perforations (26b) of one or more of second secondary plates (20b) are aligned with respect to each other along the height (Z) of the heat exchanger core (100) to form a third channel (60).

Description

TECHNICAL FIELD

[0001] The present invention relates to a core for heat exchanger, more particularly, the present invention relates to a plate type heat exchanger, such as a chiller for a vehicle.BACKGROUND OF THE INVENTION

[0002] Electric vehicles utilize a heat-exchanger, particularly, a chiller for heat dissipation from the battery pack to cool the battery pack of a vehicle. The chiller is used to cool a coolant (such as water) and the coolant is used to cool the battery. The heat exchange takes place between the coolant and the refrigerant, where coolant has a greater temperature than the refrigerant. The chiller may be the heat exchanger of a plate type. A plate type heat exchanger core is usually used in a chiller because of a compact design, lighter weight and large heat exchange area. Due to environmental concern, environmentally friendly refrigerants such as R744 are preferred over conventional HFC based refrigerants such as R32. R744 is operated at a high pressure and thus pressure drop in the refrigerant while it flows within the heat exchanger has comparatively less adverse impact on performance of the heat exchanger compared to pressure drop for synthetic refrigerants. Due to this, a higher number of passes can be configured along the height of the heat exchange core without significant penalty to efficiency caused by pressure drop. Thus, overall efficiency of the plate type heat exchanger is highly improved.

[0003] Due to space constraints, the inlet and the outlet refrigerant channels are disposed on the same side of the heat exchange core. However, if the refrigerant takes multiple passes in the height direction of the heat exchange core, when the refrigerant reaches the final pass (in height direction) it becomes challenging to retrieve the refrigerant so that it can exit the heat exchanger from the same side as the inlet of the refrigerant to the heat exchanger.OBJECT OF THE INVENTION

[0004] An object of the invention is to retrieve the refrigerant on the same side as the inlet of the refrigerant after it has undergone multiple passes of heat exchange in a height direction of the heat exchanger.

[0005] Further, an object of the invention is to maximize the heat exchange area during the final pass that the refrigerant takes inside the heat exchanger core.SUMMARY OF THE INVENTION

[0006] The invention relates to a heat exchanger that includes a plurality of primary plates, and a plurality of secondary plates, disposed alternately with respect to each other to define a height Z of the heat exchanger core. The primary plates and the secondary plates define plurality of first fluid flow passages configured to allow at least a first fluid to flow therein. The plurality of primary plates comprise at least a plurality of first primary plates each comprising at least a first aperture and a second aperture allowing the first fluid to pass therethrough. The plurality of primary plates also comprise at least a plurality of second primary plates each comprising at least a first hole and at least a second hole allowing the first fluid to pass therethrough. The plurality of primary plates further comprise at least one third primary plate each comprising at least a second opening allowing the first fluid to pass therethrough. The of secondary plates comprise at least a plurality of first secondary plates comprising at least a first orifice and a second orifice allowing the first fluid to pass therethrough. The of secondary plates also comprise at least a plurality of second secondary plates comprising at least a first perforation and at least a second perforation allowing the first fluid to pass therethrough. One or more of the first apertures, one or more of the first holes, one or more of the first orifices and one or more of the first perforation are aligned with respect to each other along the height Z of the heat exchanger core to form a first channel. One or more of the second apertures, one or more of the second holes, one or more of the second openings, one or more of the second orifices and one or more of the second perforations are aligned with respect to each other along the height Z of the heat exchanger core to form a second channel. Each second primary plate further comprises a third hole, each third primary plate further comprises a third opening and each second secondary plate further comprises a third perforation, wherein a plurality of the third holes of the plurality of second primary plates, at least one third opening of the at least one third primary plate and a plurality of the third perforations of the plurality of second secondary plates are aligned with respect to each other along the height Z of the heat exchanger core to form a third channel.

[0007] Particularly, the heat exchanger core comprises a first core layer defined at least by a plurality of the second primary plates and a plurality of second secondary plates.

[0008] Particularly, the heat exchanger core comprises a second core layer is defined at least by a plurality of the second primary plates and a plurality of second secondary plates.

[0009] Further, the heat exchanger core comprises a third core layer defined by a plurality of the first primary plates.

[0010] Specifically, at least one third primary plate is disposed between the first core layer and the second core layer.

[0011] Specifically, the first core layer and the second core layer are in fluidic communication with each other through the third channel.

[0012] Generally, the second core layer and the third core layer are in fluidic communication with each other through the first channel.

[0013] Generally, the third core layer is in fluidic communication with the second channel.

[0014] Specifically, the first core layer and the second core layer are fluidically isolated from the second channel.

[0015] Particularly, the first channel is located on the opposite side of the second channel and the third channel in a lateral direction Y of the heat exchanger core.

[0016] Generally, an intermediate plate is disposed within the first fluid flow passages to configure a uniform distribution of the first fluid in first fluid flow passages.

[0017] Particularly, the intermediate plate comprises at least one corrugation extending in a longitudinal direction X of heat exchanger core wherein the at least one corrugation is configured to allow the first fluid to flow in at least a first pass and a second pass in one of the first fluid flow passages and the fluid executes at least one U-turn while flowing therein.

[0018] Specifically, the intermediate plate comprises one or more corrugations to allow the first fluid to execute an odd number of U-turns.

[0019] More specifically, the width of the at least one of the first pass and the second pass is less than five times the width of at least one of the first channel, the second channel and the third channel.

[0020] Particularly, the intermediate plate comprises a secondary corrugation that seals the periphery of the third channel and fluidically isolates the first core layer and the second core layer from the second channel.BRIEF DESCRIPTION OF DRAWINGS

[0021] Other characteristics, details and advantages of the invention may 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 schematic representation depicting a heat exchanger core in accordance with an embodiment of the present invention. FIG. 2 illustrates a top view of the heat exchanger core of FIG. 1. FIG. 3 illustrates a sectional view of the heat exchanger core of FIG. 1 along a section line AA' depicted in FIG 2, and an enlarged view of a top portion of this sectional view, according an embodiment of the heat exchanger core of FIG. 1. FIG. 4a, FIG. 4b and FIG. 4c illustrate top views of a first primary plate, a second primary plate and a third primary plate, respectively of the heat exchanger core of FIG. 1. FIG. 5a and FIG. 5b illustrate top views of a first secondary plate and a second secondary plate, respectively of the heat exchanger core of FIG. 1. FIG. 6a illustrates a top view of an intermediate plate of the heat exchanger core of FIG. 1. Specifically, FIG. 6a illustrates a first intermediate plate used in the third core layer as depicted in the subsequent FIG. 9. FIG. 6b illustrates a top view of an alternate embodiment of the first intermediate plate of FIG. 6a. FIG. 7a illustrates a top view of an intermediate plate of the heat exchanger core of FIG. 1. Specifically, FIG. 7a illustrates a second intermediate plate used in the first core layer and the second core layer as depicted in subsequent FIG. 8 and FIG. 10. FIG. 7b illustrates a top view of an alternate embodiment of the second intermediate plate of FIG. 6a. FIG. 8 illustrates a sectional view of the heat exchanger core of FIG 1 along a section line BB' depicted in FIG 2. FIG. 9 illustrates a sectional view of the heat exchanger core of FIG 1 along a section line CC' depicted in FIG 2. FIG. 10 illustrates a sectional view of the heat exchanger core of FIG 1 along a section line DD' depicted in FIG 2. FIG. 11a, FIG. 11b, FIG. 11c and FIG. 11d illustrates schematic representation of the heat exchanger core depicting the flow pattern of a first fluid in the heat exchanger core. FIG. 11a, FIG. 11b, FIG. 11c and FIG. 11d also illustrate a top view of the first intermediate plate and the second intermediate plate to show the flow pattern of the first fluid in the respective core layers. DETAILED DESCRIPTION OF THE INVENTION

[0022] The present invention relates to a heat exchanger used primarily in a vehicle. More specifically, the invention relates to a plate type heat exchanger for cooling a coolant by allowing it to exchange heat with a cold refrigerant. A plate type heat exchanger has a heat exchanger core made up of multiple plates defining multiple channels between the plates, wherein a refrigerant and a coolant flows exchanging heat between them.

[0023] The heat exchanger core of the present invention proposes stacking multiple plates of specific shape and aperture distributions to retrieve the refrigerant from the bottom of the heat exchanger core through an outlet placed on the same side as the inlet of the refrigerant, after it has undergone multiple passes of heat exchange in a height direction of the heat exchanger core.

[0024] FIG. 1 depicts a heat exchanger core 100 according to an embodiment of the present invention. The figure further depicts the direction X, Y and Z along the length, width and height, respectively of the heat exchanger core. The directions X, Y and Z will be subsequently used in describing the invention.

[0025] FIG. 2 illustrates the top view of the heat exchanger core 100 and also depicts the section lines AA', BB', CC', DD' along which sectional views have been illustrated in further figures, to describe the components thereof.

[0026] FIG. 3. Illustrates the sectional view along the section line AA' of the heat exchanger core 100 according to an embodiment of the current invention. A depicted in the enlarged view of a top portion of the heat exchange core 100. The heat exchanger core 100 includes a plurality of primary plates 10, a plurality of secondary plates 20. Plurality of the primary plates 10 and plurality of the secondary plates 20 are disposed or stacked alternatively with respect to each other. This alternate stacking of the primary plates 10 and the secondary plates 20 define the height Z of the heat exchange core. The overall shape of the primary plates 10 and the secondary plates 20 substantially resembles a rectangle with the oblique bent edges. Thus when stacked together, the primary plates 10 and the secondary plates 20 define channels for fluid flow, wherein a first fluid and a second fluid flow in alternate channels to exchange heat between themselves. Commonly, a refrigerant and a coolant is used in such a scenario. A plurality of fluid flow passages 30 are defined by the primary plates 10 and the secondary plates 20 allowing a first fluid to flow therein. Although not illustrated, between every two fluid flow passages 30, there is a channel (not illustrated) for a second fluid to flow therein allowing heat exchange between the first fluid and the second fluid. An intermediate plate 70 is disposed within the first fluid flow passages 30 to configure a uniform distribution of the first fluid in first fluid flow passages 30. Further details about the construction of the intermediate plate 70 will discussed later in this description.

[0027] FIG. 4a, FIG. 4b and FIG. 4c illustrate three types of the primary plates 10 according to an embodiment of this invention. The primary plates 10 include one or more first primary plates 10a, one or more second primary plates 10b and one or more third primary plates 10c. Each first primary plate 10a includes a first aperture 12a and a second aperture 14a allowing the first fluid to pass therethrough. Each second primary plate 10b includes a first hole 12b a second hole 14b and a third hole 16b allowing the first fluid to pass therethrough. Each third primary plate 10c includes a second opening 14c and a third opening 16c allowing the first fluid to pass therethrough.

[0028] FIG. 5a and FIG. 5b illustrate two types of the secondary plates 20 according to an embodiment of this invention. The secondary plates 20 includes one or more first secondary plates 20a and one or more of second secondary plates 20b. Each first secondary plate 20a includes a first orifice 22a and a second orifice 24a allowing the first fluid to pass therethrough. Each second secondary plate 20b includes a first perforation 22b, a second perforation 24b and a third perforation 26b allowing the first fluid to pass therethrough.

[0029] Upon alternately aligning and stacking the different plates (10a, 10b, 10c, 20a, 20b) in a desired order, plurality of apertures, holes, openings, orifices and perforations, are aligned to form different fluid flow channels described below.

[0030] Particularly, one or more of the first apertures 12a of the first primary plates 10a, one or more of the first holes 12b of the second primary plates 10b, one or more of the first orifices 22a of the first secondary plates 20a and one or more of the first perforation 22b of the second secondary plates 20b are aligned with respect to each other along the height Z of the heat exchanger core 100 to form a first channel 40 (illustrated in FIG 8).

[0031] Similarly, one or more of the second apertures 14a of the first primary plates 10a, one or more of the second holes 14b of the second primary plates 10b, one or more of the second openings 14c of the third primary plates 10c, one or more of the second orifices 24a of the first secondary plate 20a and one or more of the second perforations 24b of the second secondary plate 20b are aligned with respect to each other along the height Z of the heat exchanger core 100 to form a second channel 50 (illustrated in FIG. 9).

[0032] Similarly, one or more of the third holes 16b one or more of second primary plates 10b, at least one third opening 16c of the at least one third primary plate 10c and one or more of the third perforations 26b of one or more of second secondary plates 20b are aligned with respect to each other along the height Z of the heat exchanger core 100 to form a third channel 60 (illustrated in FIG. 9 and FIG. 10).

[0033] FIG. 6a illustrates an intermediate plate 70 and more specifically a first intermediate plate 70a used in the third core layer 100c (depicted in the subsequent FIG. 9) of the heat exchanger core 100. FIG. 7a illustrates a second intermediate plate 70b used in the first core layer 100a and the second core layer 100b (depicted in subsequent FIG. 10) of the heat exchanger core 100. The first intermediate plate 70a and the second intermediate plate 70b (collectively intermediate plate 70) includes one of more corrugations 78. The corrugation(s) extend in a longitudinal direction X (i.e. length direction) of the heat exchanger core. The one or more corrugations 78 are configured to allow the first fluid to flow in at least a first pass A and at least a second pass B in one of the first fluid flow passages (30) and the fluid executes at least one U-turn while flowing therein. Both the first intermediate plate 70a and the second intermediate plate 70b includes a first lateral wall 71 and a second lateral wall 73 opposite (along length direction X) to the first lateral wall 71. For clarity, the first lateral wall 71 is the one proximal to the first channel 40 or the second channel 50 or the third channel 60, while the second lateral wall 73 is distal from the first channel 40 or the second channel 50 or the third channel 60. In case of a single corrugation 78, as shown in FIG. 6a and FIG. 7a, the corrugation 78 extends in the length direction X from a lateral wall 71 towards the second lateral wall 73, but terminates before the second lateral wall 73 to leave enough space for the first fluid to execute a U-turn. The corrugation 78 is substantially centrally located about the width direction Y (shown in FIG. 2) of the first intermediate plate 70a and the second intermediate plate 70b, dividing them into two substantially equal parts. The first fluid flowing in the first fluid flow passage 30 is thus guided by the corrugation 78 to take a first pass A, then takes a U-turn to change direction, and then takes a second pass B that is substantially opposite in flow direction (length direction X) than first pass A.

[0034] The first intermediate plate 70a, depicted in FIG 6a, includes a first pore 72a aligned with the first channel 40, and a second pore 74a aligned with the second channel 50.

[0035] The second intermediate plate 70b depicted in FIG. 7a, includes a first borehole 72b aligned with the first channel 40, a second borehole 74b aligned with the second channel 50, and a third borehole 76b aligned with the third channel 60.

[0036] It must be noted that corrugations 78 may extend in Z-direction towards the adjacent primary plate 10 or the secondary plate 20. The crest (or trough) of the corrugations 78 touch the adjacent primary plate 10 or the secondary plate 20 and are brazed thereto (or any other suitable sealing method) forming a fluidically sealed seam (not illustrated) that prevents any fluid flow across it. Thus, the first fluid flows along the length of the corrugation and changes direction only when the first fluid reaches the U-turn at the end of the corrugation 78.

[0037] As discussed earlier, the second intermediate plate 70b depicted in FIG. 7a, includes a second borehole 74b aligned with the second channel 50, and a third borehole 76b aligned with the third channel 60. The second intermediate plate 70b includes a secondary corrugation 78a that is disposed between the second borehole 74b and the third borehole 76b as a barrier. The secondary corrugation 78a is also brazed to the adjacent primary plate 10 and the adjacent secondary plate 20 and hence, seals the periphery of the third channel 60, fluidically isolating the first fluid flow passage 30 from the second channel 50. The second intermediate plate 70b is disposed in the first core layer 100a and the second core layer 100b and thus isolates them from the second channel 50. This is important since the second channel 50 is dedicated only to retrieve the first fluid after it has completed the passes in the third core layer 100c. Additionally, such a secondary corrugation 78b may be provided in the second intermediate plate 70b around the second borehole 74b to isolate the first fluid flow passages 30 of the first core layer 100a and the second core layer 100b, from the second channel 50.

[0038] Alternate embodiments of the first intermediate plate 70a and the second intermediate plate 70b, are depicted in FIG. 6b and FIG. 7b, respectively, and have more than one corrugations 78. The multiple corrugations 78 extend from the first lateral wall 71 and the second lateral wall 73 in alternate fashion creating more number of passes A, B, C and D. More number of such passes are possible by increasing the number of corrugations 78 and such a configuration is well within the scope of the invention. Effectively, a more number of passes promotes more uniform distribution of the fluid flow within the first fluid flow channels 30.

[0039] In one embodiment, the width of the at least one of the first pass A and the second pass B is less than five times the width of at least one of the first channel 40, the second channel 50 and the third channel 60. This limits the width of the passes to less than five times than the width of the channels (40, 50 and 60). Since the width of the passes is governed by the number of the corrugations 78 (more number of corrugations 78 indicates more number of passes with less width of each pass), more number of channels facilitate more even distribution of the first fluid in the first fluid flow passages 30 improving heat exchange efficiency.

[0040] Generally, the number of corrugations 78 are defined so that the first fluid is allowed to execute an odd number of U-turns in the first fluid flow passages 30. This is essential for having the inlet and outlet nozzles (not illustrated) of the heat exchanger core 100 on the same side (in length direction X) as after odd number of U-turns the first fluid ends up on the same side as it started from. This improves packaging efficiency and reduces assembly and maintenance time, thus saves weight, costs and improves efficiency.

[0041] FIG. 8, FIG. 9 and FIG. 10 illustrate the cross sectional views of the heat exchanger core 100 along the section line AA', BB' and CC' (shown in FIG. 2). As shown in FIG. 8, FIG. 9 and FIG. 10, the heat exchanger core 100 is divided in to a first core layer 100a, a second core layer 100b and a third core layer 100c.

[0042] The first core layer 100a includes one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately. Additionally, the first core layer 100a also includes an intermediate plate 70b disposed in each of the fluid flow passages 30 defined by one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately.

[0043] The second core layer 100b also includes one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately. Additionally, the first core layer 100a also includes an intermediate plate 70b disposed in each of the fluid flow passages 30 defined by one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately.

[0044] The third core layer is defined by one or more of the first primary plates 10a and one or more of the first secondary plates 20a with an intermediate plate 70a disposed in each of the fluid flow passages 30 defined by the first primary plates 10a and the first secondary plates 20a of this third core layer 100c.

[0045] Notably, as shown in FIG. 10, one third primary plate 10c is disposed between and separates the first core layer 100a and the second core layer 100b. Since the third primary plate 10c has no opening aligned with the first channel 40, the first fluid that enters the first channel 40 is obstructed from flowing in the Z-direction and directed to flow into the fluid flow passages 30 of the first core layer 100a. Notably, the third primary plate divides the first channel 40 in to a top first channel 40a of the first core layer 100a and a bottom first channel 40b extending between and connecting the second core layer 100b and third core layer 100c. In the first core layer 100a, the first fluid flows along the entire volume of the first fluid flow passages 30. Within the fluid flow passages 30, the first fluid takes multiple U-turns, which are substantially 180 degree turns in the fluid flow direction facilitated by the corrugations 78 of the third plate 70 disposed with the first fluid flow passage 30. The first core layer 100a and the second core layer 100b are in fluidic communication with each other through the third channel 60. The first fluid is conveyed from the first core layer 100a to the second core layer 100b through the third channel 60. The top most plate of the third core layer is the first primary channel that is devoid of any aperture aligned with the third channel 60 of the second core layer 100b. Thus, the first fluid gets obstructed from flowing in the Z-direction once again and is directed to flow into the first fluid flow passages 30 of the second core layer 100b. Within the first fluid flow passages 30 of the second core layer 100b, the first fluid flows in a similar manner as in the first core layer 100a but in the opposite flow direction, executing multiple U-turns and arrives at the bottom first channel 40b. The first channel 40, and more particularly the bottom first channel 40b enables fluidic communication between the second core layer 100b and the third core layer 100c. The first fluid finally enters the third core layer 100c after being obstructed in Z-direction by the bottom cover (not illustrated), flows through the first fluid flow channels 30 of the third core layer 100c executing one or more U-turns similar to that of the second core layer 100b but in opposite flow direction. Finally, the first fluid after flowing through the third core layer 100c, arrives at the second channel 50. The third core layer 100c is in fluidic communication with the second channel 50. The second channel 50 thus retrieves the first fluid from the third core layer 100c to the top of the heat exchanger core 100 from where it is extracted using an outlet nozzle (not illustrated) disposed on top of the heat exchanger core 100.

[0046] As evident from FIG. 8, FIG. 9 and FIG. 10, the first channel 40 is located on the opposite side (along lateral direction Y of the heat exchanger core 100) of the second channel 50 and the third channel 60.

[0047] As already explained above, it should be noted that the first core layer 100a and the second core layer 100b are fluidically isolated from the second channel 50 and thus fluid from the first core layer 100a and the second core layer 100b does not ingress into the second channel 50. This enables retrieving the first fluid from the third core layer 100c.

[0048] FIG. 11 (FIG. 11a, FIG. 11b, FIG. 11c and FIG. 11d) is a schematic diagram showing the flow pattern of the first fluid in the heat exchange core 100, depicting the vertical movement in the channels (40, 50 and 60) and horizontal movement along the intermediate plates (70 and 70b) in the first fluid flow passages 30. The first fluid enters the heat exchanger core 100 through the inlet and the enters the first channel 40 particularly the top first channel 40a, is obstructed in Z-direction by the third plate 10c, then enters the first fluid flow passages 30 of the first core layer 100a taking requisite number of U-turns guided by the first intermediate plate 70b and reaches the third channel 30. Since the first core layer 100a is fluidically connected to the second core layer 100b via the third channel 60, the first fluid enters the second core layer 100b (as shown in FIG. 11b). Notably, the corrugation 78a prevents the first fluid from entering the second channel 50 in the first core layer 100a and the second core layer 100b. After completing the passes through the first fluid flow passages 30 of the second core layer (in reverse direction to that of the first core layer 100a), the first fluid arrives at the first channel 40, more particularly the bottom first channel 40b. Since the bottom first channel 40b fluidically connects the second core layer 100b and the third core layer 100c, the fluid enters the third core layer 100c. Since the fluid is now obstructed in Z-direction by the bottom cover, the first fluid enters the first fluid flow passages 30 of the third core layer 100c wherein the first fluid takes a requisite odd number of U-turns facilitated by the first intermediate plate 70a (shown in FIG. 11c) and reaches the second channel 50 and moves through the same to the outlet (since the second channel 50 is isolated from the first and the second core layers 100a and 100b). In the Figures 11a, 11b and 11c, the direction P (indicated by ⊗ mark) indicates fluid traveling into the plane and direction Q (indicated by ⊙ mark) represents fluid flowing out of the plane, to depict the flow direction when viewed from a front-sectional view.

[0049] The invention has been described with respect to only three core layers, however, a person skilled in the art will appreciate that the same concept can be applied for more number of core layers (i.e. more number of passes in the vertical direction of the heat exchanger) and such variation is fully under the scope of this invention. In this description, the third core layer 100c is the final core layer in which the first fluid flows, however, more number of are possible within the scope of this invention and in such as case the term "third core layer" would be analogous to the last layer.

[0050] The terms "length direction", "width direction" and "height direction", "top", "bottom", and the like have been used in this description for the sake of explaining the correlation between different parts of the system as proposed by the present invention. A person skilled in the art will appreciate that the heat exchanger 100, as described in the various embodiments discussed above, may be used in any orientation and in such a case, the terms mentioned above may suitably change without compromising the essence of the invention and such change of orientation does not depart from the scope of the invention.

[0051] Further, the invention shall not be limited to the means and configurations described and illustrated in this patent specification, and shall also extend to any equivalent means or configuration described and illustrated herein, and to any technical combination operating such means. Persons having ordinary skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims, hereinafter introduced, are interpreted to include all such modifications, permutations, additions and sub-combinations and are within their true spirit and scope of this invention.

Examples

Embodiment Construction

[0022]The present invention relates to a heat exchanger used primarily in a vehicle. More specifically, the invention relates to a plate type heat exchanger for cooling a coolant by allowing it to exchange heat with a cold refrigerant. A plate type heat exchanger has a heat exchanger core made up of multiple plates defining multiple channels between the plates, wherein a refrigerant and a coolant flows exchanging heat between them.

[0023]The heat exchanger core of the present invention proposes stacking multiple plates of specific shape and aperture distributions to retrieve the refrigerant from the bottom of the heat exchanger core through an outlet placed on the same side as the inlet of the refrigerant, after it has undergone multiple passes of heat exchange in a height direction of the heat exchanger core.

[0024]FIG. 1 depicts a heat exchanger core 100 according to an embodiment of the present invention. The figure further depicts the direction X, Y and Z along the length, width a...

TECHNICAL FIELD

[0001] The present invention relates to a core for heat exchanger, more particularly, the present invention relates to a plate type heat exchanger, such as a chiller for a vehicle.BACKGROUND OF THE INVENTION

[0002] Electric vehicles utilize a heat-exchanger, particularly, a chiller for heat dissipation from the battery pack to cool the battery pack of a vehicle. The chiller is used to cool a coolant (such as water) and the coolant is used to cool the battery. The heat exchange takes place between the coolant and the refrigerant, where coolant has a greater temperature than the refrigerant. The chiller may be the heat exchanger of a plate type. A plate type heat exchanger core is usually used in a chiller because of a compact design, lighter weight and large heat exchange area. Due to environmental concern, environmentally friendly refrigerants such as R744 are preferred over conventional HFC based refrigerants such as R32. R744 is operated at a high pressure and thus pressure drop in the refrigerant while it flows within the heat exchanger has comparatively less adverse impact on performance of the heat exchanger compared to pressure drop for synthetic refrigerants. Due to this, a higher number of passes can be configured along the height of the heat exchange core without significant penalty to efficiency caused by pressure drop. Thus, overall efficiency of the plate type heat exchanger is highly improved.

[0003] Due to space constraints, the inlet and the outlet refrigerant channels are disposed on the same side of the heat exchange core. However, if the refrigerant takes multiple passes in the height direction of the heat exchange core, when the refrigerant reaches the final pass (in height direction) it becomes challenging to retrieve the refrigerant so that it can exit the heat exchanger from the same side as the inlet of the refrigerant to the heat exchanger.OBJECT OF THE INVENTION

[0004] An object of the invention is to retrieve the refrigerant on the same side as the inlet of the refrigerant after it has undergone multiple passes of heat exchange in a height direction of the heat exchanger.

[0005] Further, an object of the invention is to maximize the heat exchange area during the final pass that the refrigerant takes inside the heat exchanger core.SUMMARY OF THE INVENTION

[0006] The invention relates to a heat exchanger that includes a plurality of primary plates, and a plurality of secondary plates, disposed alternately with respect to each other to define a height Z of the heat exchanger core. The primary plates and the secondary plates define plurality of first fluid flow passages configured to allow at least a first fluid to flow therein. The plurality of primary plates comprise at least a plurality of first primary plates each comprising at least a first aperture and a second aperture allowing the first fluid to pass therethrough. The plurality of primary plates also comprise at least a plurality of second primary plates each comprising at least a first hole and at least a second hole allowing the first fluid to pass therethrough. The plurality of primary plates further comprise at least one third primary plate each comprising at least a second opening allowing the first fluid to pass therethrough. The of secondary plates comprise at least a plurality of first secondary plates comprising at least a first orifice and a second orifice allowing the first fluid to pass therethrough. The of secondary plates also comprise at least a plurality of second secondary plates comprising at least a first perforation and at least a second perforation allowing the first fluid to pass therethrough. One or more of the first apertures, one or more of the first holes, one or more of the first orifices and one or more of the first perforation are aligned with respect to each other along the height Z of the heat exchanger core to form a first channel. One or more of the second apertures, one or more of the second holes, one or more of the second openings, one or more of the second orifices and one or more of the second perforations are aligned with respect to each other along the height Z of the heat exchanger core to form a second channel. Each second primary plate further comprises a third hole, each third primary plate further comprises a third opening and each second secondary plate further comprises a third perforation, wherein a plurality of the third holes of the plurality of second primary plates, at least one third opening of the at least one third primary plate and a plurality of the third perforations of the plurality of second secondary plates are aligned with respect to each other along the height Z of the heat exchanger core to form a third channel.

[0007] Particularly, the heat exchanger core comprises a first core layer defined at least by a plurality of the second primary plates and a plurality of second secondary plates.

[0008] Particularly, the heat exchanger core comprises a second core layer is defined at least by a plurality of the second primary plates and a plurality of second secondary plates.

[0009] Further, the heat exchanger core comprises a third core layer defined by a plurality of the first primary plates.

[0010] Specifically, at least one third primary plate is disposed between the first core layer and the second core layer.

[0011] Specifically, the first core layer and the second core layer are in fluidic communication with each other through the third channel.

[0012] Generally, the second core layer and the third core layer are in fluidic communication with each other through the first channel.

[0013] Generally, the third core layer is in fluidic communication with the second channel.

[0014] Specifically, the first core layer and the second core layer are fluidically isolated from the second channel.

[0015] Particularly, the first channel is located on the opposite side of the second channel and the third channel in a lateral direction Y of the heat exchanger core.

[0016] Generally, an intermediate plate is disposed within the first fluid flow passages to configure a uniform distribution of the first fluid in first fluid flow passages.

[0017] Particularly, the intermediate plate comprises at least one corrugation extending in a longitudinal direction X of heat exchanger core wherein the at least one corrugation is configured to allow the first fluid to flow in at least a first pass and a second pass in one of the first fluid flow passages and the fluid executes at least one U-turn while flowing therein.

[0018] Specifically, the intermediate plate comprises one or more corrugations to allow the first fluid to execute an odd number of U-turns.

[0019] More specifically, the width of the at least one of the first pass and the second pass is less than five times the width of at least one of the first channel, the second channel and the third channel.

[0020] Particularly, the intermediate plate comprises a secondary corrugation that seals the periphery of the third channel and fluidically isolates the first core layer and the second core layer from the second channel.BRIEF DESCRIPTION OF DRAWINGS

[0021] Other characteristics, details and advantages of the invention may 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 schematic representation depicting a heat exchanger core in accordance with an embodiment of the present invention. FIG. 2 illustrates a top view of the heat exchanger core of FIG. 1. FIG. 3 illustrates a sectional view of the heat exchanger core of FIG. 1 along a section line AA' depicted in FIG 2, and an enlarged view of a top portion of this sectional view, according an embodiment of the heat exchanger core of FIG. 1. FIG. 4a, FIG. 4b and FIG. 4c illustrate top views of a first primary plate, a second primary plate and a third primary plate, respectively of the heat exchanger core of FIG. 1. FIG. 5a and FIG. 5b illustrate top views of a first secondary plate and a second secondary plate, respectively of the heat exchanger core of FIG. 1. FIG. 6a illustrates a top view of an intermediate plate of the heat exchanger core of FIG. 1. Specifically, FIG. 6a illustrates a first intermediate plate used in the third core layer as depicted in the subsequent FIG. 9. FIG. 6b illustrates a top view of an alternate embodiment of the first intermediate plate of FIG. 6a. FIG. 7a illustrates a top view of an intermediate plate of the heat exchanger core of FIG. 1. Specifically, FIG. 7a illustrates a second intermediate plate used in the first core layer and the second core layer as depicted in subsequent FIG. 8 and FIG. 10. FIG. 7b illustrates a top view of an alternate embodiment of the second intermediate plate of FIG. 6a. FIG. 8 illustrates a sectional view of the heat exchanger core of FIG 1 along a section line BB' depicted in FIG 2. FIG. 9 illustrates a sectional view of the heat exchanger core of FIG 1 along a section line CC' depicted in FIG 2. FIG. 10 illustrates a sectional view of the heat exchanger core of FIG 1 along a section line DD' depicted in FIG 2. FIG. 11a, FIG. 11b, FIG. 11c and FIG. 11d illustrates schematic representation of the heat exchanger core depicting the flow pattern of a first fluid in the heat exchanger core. FIG. 11a, FIG. 11b, FIG. 11c and FIG. 11d also illustrate a top view of the first intermediate plate and the second intermediate plate to show the flow pattern of the first fluid in the respective core layers. DETAILED DESCRIPTION OF THE INVENTION

[0022] The present invention relates to a heat exchanger used primarily in a vehicle. More specifically, the invention relates to a plate type heat exchanger for cooling a coolant by allowing it to exchange heat with a cold refrigerant. A plate type heat exchanger has a heat exchanger core made up of multiple plates defining multiple channels between the plates, wherein a refrigerant and a coolant flows exchanging heat between them.

[0023] The heat exchanger core of the present invention proposes stacking multiple plates of specific shape and aperture distributions to retrieve the refrigerant from the bottom of the heat exchanger core through an outlet placed on the same side as the inlet of the refrigerant, after it has undergone multiple passes of heat exchange in a height direction of the heat exchanger core.

[0024] FIG. 1 depicts a heat exchanger core 100 according to an embodiment of the present invention. The figure further depicts the direction X, Y and Z along the length, width and height, respectively of the heat exchanger core. The directions X, Y and Z will be subsequently used in describing the invention.

[0025] FIG. 2 illustrates the top view of the heat exchanger core 100 and also depicts the section lines AA', BB', CC', DD' along which sectional views have been illustrated in further figures, to describe the components thereof.

[0026] FIG. 3. Illustrates the sectional view along the section line AA' of the heat exchanger core 100 according to an embodiment of the current invention. A depicted in the enlarged view of a top portion of the heat exchange core 100. The heat exchanger core 100 includes a plurality of primary plates 10, a plurality of secondary plates 20. Plurality of the primary plates 10 and plurality of the secondary plates 20 are disposed or stacked alternatively with respect to each other. This alternate stacking of the primary plates 10 and the secondary plates 20 define the height Z of the heat exchange core. The overall shape of the primary plates 10 and the secondary plates 20 substantially resembles a rectangle with the oblique bent edges. Thus when stacked together, the primary plates 10 and the secondary plates 20 define channels for fluid flow, wherein a first fluid and a second fluid flow in alternate channels to exchange heat between themselves. Commonly, a refrigerant and a coolant is used in such a scenario. A plurality of fluid flow passages 30 are defined by the primary plates 10 and the secondary plates 20 allowing a first fluid to flow therein. Although not illustrated, between every two fluid flow passages 30, there is a channel (not illustrated) for a second fluid to flow therein allowing heat exchange between the first fluid and the second fluid. An intermediate plate 70 is disposed within the first fluid flow passages 30 to configure a uniform distribution of the first fluid in first fluid flow passages 30. Further details about the construction of the intermediate plate 70 will discussed later in this description.

[0027] FIG. 4a, FIG. 4b and FIG. 4c illustrate three types of the primary plates 10 according to an embodiment of this invention. The primary plates 10 include one or more first primary plates 10a, one or more second primary plates 10b and one or more third primary plates 10c. Each first primary plate 10a includes a first aperture 12a and a second aperture 14a allowing the first fluid to pass therethrough. Each second primary plate 10b includes a first hole 12b a second hole 14b and a third hole 16b allowing the first fluid to pass therethrough. Each third primary plate 10c includes a second opening 14c and a third opening 16c allowing the first fluid to pass therethrough.

[0028] FIG. 5a and FIG. 5b illustrate two types of the secondary plates 20 according to an embodiment of this invention. The secondary plates 20 includes one or more first secondary plates 20a and one or more of second secondary plates 20b. Each first secondary plate 20a includes a first orifice 22a and a second orifice 24a allowing the first fluid to pass therethrough. Each second secondary plate 20b includes a first perforation 22b, a second perforation 24b and a third perforation 26b allowing the first fluid to pass therethrough.

[0029] Upon alternately aligning and stacking the different plates (10a, 10b, 10c, 20a, 20b) in a desired order, plurality of apertures, holes, openings, orifices and perforations, are aligned to form different fluid flow channels described below.

[0030] Particularly, one or more of the first apertures 12a of the first primary plates 10a, one or more of the first holes 12b of the second primary plates 10b, one or more of the first orifices 22a of the first secondary plates 20a and one or more of the first perforation 22b of the second secondary plates 20b are aligned with respect to each other along the height Z of the heat exchanger core 100 to form a first channel 40 (illustrated in FIG 8).

[0031] Similarly, one or more of the second apertures 14a of the first primary plates 10a, one or more of the second holes 14b of the second primary plates 10b, one or more of the second openings 14c of the third primary plates 10c, one or more of the second orifices 24a of the first secondary plate 20a and one or more of the second perforations 24b of the second secondary plate 20b are aligned with respect to each other along the height Z of the heat exchanger core 100 to form a second channel 50 (illustrated in FIG. 9).

[0032] Similarly, one or more of the third holes 16b one or more of second primary plates 10b, at least one third opening 16c of the at least one third primary plate 10c and one or more of the third perforations 26b of one or more of second secondary plates 20b are aligned with respect to each other along the height Z of the heat exchanger core 100 to form a third channel 60 (illustrated in FIG. 9 and FIG. 10).

[0033] FIG. 6a illustrates an intermediate plate 70 and more specifically a first intermediate plate 70a used in the third core layer 100c (depicted in the subsequent FIG. 9) of the heat exchanger core 100. FIG. 7a illustrates a second intermediate plate 70b used in the first core layer 100a and the second core layer 100b (depicted in subsequent FIG. 10) of the heat exchanger core 100. The first intermediate plate 70a and the second intermediate plate 70b (collectively intermediate plate 70) includes one of more corrugations 78. The corrugation(s) extend in a longitudinal direction X (i.e. length direction) of the heat exchanger core. The one or more corrugations 78 are configured to allow the first fluid to flow in at least a first pass A and at least a second pass B in one of the first fluid flow passages (30) and the fluid executes at least one U-turn while flowing therein. Both the first intermediate plate 70a and the second intermediate plate 70b includes a first lateral wall 71 and a second lateral wall 73 opposite (along length direction X) to the first lateral wall 71. For clarity, the first lateral wall 71 is the one proximal to the first channel 40 or the second channel 50 or the third channel 60, while the second lateral wall 73 is distal from the first channel 40 or the second channel 50 or the third channel 60. In case of a single corrugation 78, as shown in FIG. 6a and FIG. 7a, the corrugation 78 extends in the length direction X from a lateral wall 71 towards the second lateral wall 73, but terminates before the second lateral wall 73 to leave enough space for the first fluid to execute a U-turn. The corrugation 78 is substantially centrally located about the width direction Y (shown in FIG. 2) of the first intermediate plate 70a and the second intermediate plate 70b, dividing them into two substantially equal parts. The first fluid flowing in the first fluid flow passage 30 is thus guided by the corrugation 78 to take a first pass A, then takes a U-turn to change direction, and then takes a second pass B that is substantially opposite in flow direction (length direction X) than first pass A.

[0034] The first intermediate plate 70a, depicted in FIG 6a, includes a first pore 72a aligned with the first channel 40, and a second pore 74a aligned with the second channel 50.

[0035] The second intermediate plate 70b depicted in FIG. 7a, includes a first borehole 72b aligned with the first channel 40, a second borehole 74b aligned with the second channel 50, and a third borehole 76b aligned with the third channel 60.

[0036] It must be noted that corrugations 78 may extend in Z-direction towards the adjacent primary plate 10 or the secondary plate 20. The crest (or trough) of the corrugations 78 touch the adjacent primary plate 10 or the secondary plate 20 and are brazed thereto (or any other suitable sealing method) forming a fluidically sealed seam (not illustrated) that prevents any fluid flow across it. Thus, the first fluid flows along the length of the corrugation and changes direction only when the first fluid reaches the U-turn at the end of the corrugation 78.

[0037] As discussed earlier, the second intermediate plate 70b depicted in FIG. 7a, includes a second borehole 74b aligned with the second channel 50, and a third borehole 76b aligned with the third channel 60. The second intermediate plate 70b includes a secondary corrugation 78a that is disposed between the second borehole 74b and the third borehole 76b as a barrier. The secondary corrugation 78a is also brazed to the adjacent primary plate 10 and the adjacent secondary plate 20 and hence, seals the periphery of the third channel 60, fluidically isolating the first fluid flow passage 30 from the second channel 50. The second intermediate plate 70b is disposed in the first core layer 100a and the second core layer 100b and thus isolates them from the second channel 50. This is important since the second channel 50 is dedicated only to retrieve the first fluid after it has completed the passes in the third core layer 100c. Additionally, such a secondary corrugation 78b may be provided in the second intermediate plate 70b around the second borehole 74b to isolate the first fluid flow passages 30 of the first core layer 100a and the second core layer 100b, from the second channel 50.

[0038] Alternate embodiments of the first intermediate plate 70a and the second intermediate plate 70b, are depicted in FIG. 6b and FIG. 7b, respectively, and have more than one corrugations 78. The multiple corrugations 78 extend from the first lateral wall 71 and the second lateral wall 73 in alternate fashion creating more number of passes A, B, C and D. More number of such passes are possible by increasing the number of corrugations 78 and such a configuration is well within the scope of the invention. Effectively, a more number of passes promotes more uniform distribution of the fluid flow within the first fluid flow channels 30.

[0039] In one embodiment, the width of the at least one of the first pass A and the second pass B is less than five times the width of at least one of the first channel 40, the second channel 50 and the third channel 60. This limits the width of the passes to less than five times than the width of the channels (40, 50 and 60). Since the width of the passes is governed by the number of the corrugations 78 (more number of corrugations 78 indicates more number of passes with less width of each pass), more number of channels facilitate more even distribution of the first fluid in the first fluid flow passages 30 improving heat exchange efficiency.

[0040] Generally, the number of corrugations 78 are defined so that the first fluid is allowed to execute an odd number of U-turns in the first fluid flow passages 30. This is essential for having the inlet and outlet nozzles (not illustrated) of the heat exchanger core 100 on the same side (in length direction X) as after odd number of U-turns the first fluid ends up on the same side as it started from. This improves packaging efficiency and reduces assembly and maintenance time, thus saves weight, costs and improves efficiency.

[0041] FIG. 8, FIG. 9 and FIG. 10 illustrate the cross sectional views of the heat exchanger core 100 along the section line AA', BB' and CC' (shown in FIG. 2). As shown in FIG. 8, FIG. 9 and FIG. 10, the heat exchanger core 100 is divided in to a first core layer 100a, a second core layer 100b and a third core layer 100c.

[0042] The first core layer 100a includes one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately. Additionally, the first core layer 100a also includes an intermediate plate 70b disposed in each of the fluid flow passages 30 defined by one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately.

[0043] The second core layer 100b also includes one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately. Additionally, the first core layer 100a also includes an intermediate plate 70b disposed in each of the fluid flow passages 30 defined by one or more of the second primary plates 10b and one or more of second secondary plates 20b arranged alternately.

[0044] The third core layer is defined by one or more of the first primary plates 10a and one or more of the first secondary plates 20a with an intermediate plate 70a disposed in each of the fluid flow passages 30 defined by the first primary plates 10a and the first secondary plates 20a of this third core layer 100c.

[0045] Notably, as shown in FIG. 10, one third primary plate 10c is disposed between and separates the first core layer 100a and the second core layer 100b. Since the third primary plate 10c has no opening aligned with the first channel 40, the first fluid that enters the first channel 40 is obstructed from flowing in the Z-direction and directed to flow into the fluid flow passages 30 of the first core layer 100a. Notably, the third primary plate divides the first channel 40 in to a top first channel 40a of the first core layer 100a and a bottom first channel 40b extending between and connecting the second core layer 100b and third core layer 100c. In the first core layer 100a, the first fluid flows along the entire volume of the first fluid flow passages 30. Within the fluid flow passages 30, the first fluid takes multiple U-turns, which are substantially 180 degree turns in the fluid flow direction facilitated by the corrugations 78 of the third plate 70 disposed with the first fluid flow passage 30. The first core layer 100a and the second core layer 100b are in fluidic communication with each other through the third channel 60. The first fluid is conveyed from the first core layer 100a to the second core layer 100b through the third channel 60. The top most plate of the third core layer is the first primary channel that is devoid of any aperture aligned with the third channel 60 of the second core layer 100b. Thus, the first fluid gets obstructed from flowing in the Z-direction once again and is directed to flow into the first fluid flow passages 30 of the second core layer 100b. Within the first fluid flow passages 30 of the second core layer 100b, the first fluid flows in a similar manner as in the first core layer 100a but in the opposite flow direction, executing multiple U-turns and arrives at the bottom first channel 40b. The first channel 40, and more particularly the bottom first channel 40b enables fluidic communication between the second core layer 100b and the third core layer 100c. The first fluid finally enters the third core layer 100c after being obstructed in Z-direction by the bottom cover (not illustrated), flows through the first fluid flow channels 30 of the third core layer 100c executing one or more U-turns similar to that of the second core layer 100b but in opposite flow direction. Finally, the first fluid after flowing through the third core layer 100c, arrives at the second channel 50. The third core layer 100c is in fluidic communication with the second channel 50. The second channel 50 thus retrieves the first fluid from the third core layer 100c to the top of the heat exchanger core 100 from where it is extracted using an outlet nozzle (not illustrated) disposed on top of the heat exchanger core 100.

[0046] As evident from FIG. 8, FIG. 9 and FIG. 10, the first channel 40 is located on the opposite side (along lateral direction Y of the heat exchanger core 100) of the second channel 50 and the third channel 60.

[0047] As already explained above, it should be noted that the first core layer 100a and the second core layer 100b are fluidically isolated from the second channel 50 and thus fluid from the first core layer 100a and the second core layer 100b does not ingress into the second channel 50. This enables retrieving the first fluid from the third core layer 100c.

[0048] FIG. 11 (FIG. 11a, FIG. 11b, FIG. 11c and FIG. 11d) is a schematic diagram showing the flow pattern of the first fluid in the heat exchange core 100, depicting the vertical movement in the channels (40, 50 and 60) and horizontal movement along the intermediate plates (70 and 70b) in the first fluid flow passages 30. The first fluid enters the heat exchanger core 100 through the inlet and the enters the first channel 40 particularly the top first channel 40a, is obstructed in Z-direction by the third plate 10c, then enters the first fluid flow passages 30 of the first core layer 100a taking requisite number of U-turns guided by the first intermediate plate 70b and reaches the third channel 30. Since the first core layer 100a is fluidically connected to the second core layer 100b via the third channel 60, the first fluid enters the second core layer 100b (as shown in FIG. 11b). Notably, the corrugation 78a prevents the first fluid from entering the second channel 50 in the first core layer 100a and the second core layer 100b. After completing the passes through the first fluid flow passages 30 of the second core layer (in reverse direction to that of the first core layer 100a), the first fluid arrives at the first channel 40, more particularly the bottom first channel 40b. Since the bottom first channel 40b fluidically connects the second core layer 100b and the third core layer 100c, the fluid enters the third core layer 100c. Since the fluid is now obstructed in Z-direction by the bottom cover, the first fluid enters the first fluid flow passages 30 of the third core layer 100c wherein the first fluid takes a requisite odd number of U-turns facilitated by the first intermediate plate 70a (shown in FIG. 11c) and reaches the second channel 50 and moves through the same to the outlet (since the second channel 50 is isolated from the first and the second core layers 100a and 100b). In the Figures 11a, 11b and 11c, the direction P (indicated by ⊗ mark) indicates fluid traveling into the plane and direction Q (indicated by ⊙ mark) represents fluid flowing out of the plane, to depict the flow direction when viewed from a front-sectional view.

[0049] The invention has been described with respect to only three core layers, however, a person skilled in the art will appreciate that the same concept can be applied for more number of core layers (i.e. more number of passes in the vertical direction of the heat exchanger) and such variation is fully under the scope of this invention. In this description, the third core layer 100c is the final core layer in which the first fluid flows, however, more number of are possible within the scope of this invention and in such as case the term "third core layer" would be analogous to the last layer.

[0050] The terms "length direction", "width direction" and "height direction", "top", "bottom", and the like have been used in this description for the sake of explaining the correlation between different parts of the system as proposed by the present invention. A person skilled in the art will appreciate that the heat exchanger 100, as described in the various embodiments discussed above, may be used in any orientation and in such a case, the terms mentioned above may suitably change without compromising the essence of the invention and such change of orientation does not depart from the scope of the invention.

[0051] Further, the invention shall not be limited to the means and configurations described and illustrated in this patent specification, and shall also extend to any equivalent means or configuration described and illustrated herein, and to any technical combination operating such means. Persons having ordinary skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims, hereinafter introduced, are interpreted to include all such modifications, permutations, additions and sub-combinations and are within their true spirit and scope of this invention.

Examples

Embodiment Construction

[0022]The present invention relates to a heat exchanger used primarily in a vehicle. More specifically, the invention relates to a plate type heat exchanger for cooling a coolant by allowing it to exchange heat with a cold refrigerant. A plate type heat exchanger has a heat exchanger core made up of multiple plates defining multiple channels between the plates, wherein a refrigerant and a coolant flows exchanging heat between them.

[0023]The heat exchanger core of the present invention proposes stacking multiple plates of specific shape and aperture distributions to retrieve the refrigerant from the bottom of the heat exchanger core through an outlet placed on the same side as the inlet of the refrigerant, after it has undergone multiple passes of heat exchange in a height direction of the heat exchanger core.

[0024]FIG. 1 depicts a heat exchanger core 100 according to an embodiment of the present invention. The figure further depicts the direction X, Y and Z along the length, width a...

Claims

1. A heat exchanger core (100) comprising : a plurality of primary plates (10), and a plurality of secondary plates (20), disposed alternately with respect to each other to define a height (Z) of the heat exchanger core (100), wherein, the primary plates (10) and the secondary plates (20) define plurality of first fluid flow passages (30) configured to allow at least a first fluid to flow therein, wherein, the plurality of primary plates (10) comprise: • at least a plurality of first primary plates (10a) each comprising at least a first aperture (12a) and a second aperture (14a) allowing the first fluid to pass therethrough, • at least a plurality of second primary plates (10b) each comprising at least a first hole (12b) and at least a second hole (14b) allowing the first fluid to pass therethrough, • at least one third primary plate (10c) each comprising at least a second opening (14c) allowing the first fluid to pass therethrough, wherein the of secondary plates (20) comprise : • at least a plurality of first secondary plates (20a) comprising at least a first orifice (22a) and a second orifice (24a) allowing the first fluid to pass therethrough, • at least a plurality of second secondary plates (20b) comprising at least a first perforation (22b) and at least a second perforation (24b) allowing the first fluid to pass therethrough, wherein one or more of the first apertures (12a), one or more of the first holes (12b), one or more of the first orifices (22a) and one or more of the first perforation (22b) are aligned with respect to each other along the height (Z) of the heat exchanger core (100) to form a first channel (40), wherein one or more of the second apertures (14a), one or more of the second holes (14b), one or more of the second openings (14c), one or more of the second orifices (24a) and one or more of the second perforations (24b) are aligned with respect to each other along the height (Z) of the heat exchanger core (100) to form a second channel (50), characterised in that, each second primary plate (10b) further comprises a third hole (16b), each third primary plate (10c) further comprises a third opening (16c) and each second secondary plate (20b) further comprises a third perforation (26b), wherein one or more of the third holes (16b) one or more of second primary plates (10b), at least one third opening (16c) of the at least one third primary plate (10c) and one or more of the third perforations (26b) of one or more of second secondary plates (20b) are aligned with respect to each other along the height (Z) of the heat exchanger core (100) to form a third channel (60).

2. The heat exchanger core (100) as claimed in the previous claim wherein a first core layer (100a) is defined at least by a plurality of the second primary plates (10b) and a plurality of second secondary plates (20b).

3. The heat exchanger core (100) as claimed in any of the preceding claims wherein a second core layer (100b) is defined at least by a plurality of the second primary plates (10b) and a plurality of second secondary plates (20b).

4. The heat exchanger core (100) as claimed in any of the preceding claims wherein one or more of the first primary plates (10a) and one or more of the first secondary plates (20a) define a third core layer (100c).

5. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 2 and claim 3 wherein, at least one third primary plate (10c) is disposed between the first core layer (100a) and the second core layer (100b).

6. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 2 and claim 3 wherein, the first core layer (100a) and the second core layer (100b) are in fluidic communication with each other through the third channel (60).

7. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 3 and claim 4 wherein, the second core layer (100b) and the third core layer (100c) are in fluidic communication with each other through the first channel (40).

8. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 4 wherein, the third core layer (100c) is in fluidic communication with the second channel (50).

9. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 2 and claim 3 wherein, the first core layer (100a) and the second core layer (100b) are fluidically isolated from the second channel (50).

10. The heat exchanger core (100) as claimed in any of the preceding claims wherein, the first channel (40) is located on the opposite side of the second channel (50) and the third channel (60) in a lateral direction (Y) of the heat exchanger core (100).

11. The heat exchanger core (100) as claimed in any of the preceding claims wherein, an intermediate plate (70, 70a, 70b) is disposed within the first fluid flow passages (30) to configure a uniform distribution of the first fluid in first fluid flow passages (30).

12. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 11 wherein, the intermediate plate (70, 70a, 70b) comprises at least one corrugation (78) extending in a longitudinal direction (X) of the heat exchanger core (100) wherein the at least one corrugation (78) is configured to allow the first fluid to flow in at least a first pass (A) and at least a second pass (B) in the first fluid flow passages (30) and the fluid executes at least one U-turn while flowing therein.

13. The heat exchanger core (100) as claimed in the previous claim wherein, the intermediate plate (70, 70a, 70b) comprises one or more corrugations (78) to allow the first fluid to execute an odd number of U-turns.

14. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 12 wherein, the width of the at least one of the first pass (A) and the second pass (B) is less than five times the width of at least one of the first channel (40), the second channel (50) and the third channel (60).

15. The heat exchanger core (100) as claimed in any of the preceding claims in combination with claim 9 and claim 12 wherein, the intermediate plate (70b) comprises a secondary corrugation (78a) that seals the periphery of the third channel (60) and fluidically isolates the first core layer (100a) and the second core layer (100b) from the second channel (50).

Images