EP4624206A1

EP4624206A1 - A heat exchanger assembly

Info

Publication number: EP4624206A1
Application number: EP24166463.0A
Authority: EP
Inventors: Damian PAWLAK; Ewelina CZERLUNCZAKIEWICZ; Bartlomiej GRZESZCZAK
Original assignee: Valeo Systemes Thermiques SAS
Current assignee: Valeo Electrification SAS
Priority date: 2024-03-26
Filing date: 2024-03-26
Publication date: 2025-10-01
Also published as: WO2025201805A1

Abstract

The object of the invention is, inter alia, a heat exchanger assembly (1000) for heat exchange between a first fluid and at least a second fluid comprising: a first heat exchanger (100) configured for flow of a second fluid therein, and a second heat exchanger (200), the heat exchanger assembly (1000) further comprising a substantially helical portion (500), the helical portion (500) being configured to provide a fluidal communication between the first heat exchanger (100) and the second heat exchanger (200).

Description

FIELD OF THE INVENTION

The invention relates to a heat exchanger assembly. In particular, the invention relates to heat exchanger assembly for a motor vehicle.

BACKGROUND OF THE INVENTION

The modern vehicles, including internal combustion engines, electric vehicles, and hybrid vehicles requires application of multiple heat exchangers in order to meet requirements in terms of performance, price and packaging. It is even more challenging to provide competitive assembly when the system aims to be environmeantally friendly by use of specific fluids such as R744 or R290. This puts more constrains on the fluid-tightness and ability to withstand high pressure.
Oftentimes the assembly requires two gascoolers (particularly: air gas coolers) integrated in one module. Additionally, the other heat exchanger, e.g. low temperature radiator may be integrated in the same assembly, in-between the gas coolers.
Therefore the connector needs to ensure tight connection between gascoolers in any conditions, during assembly and in operation of the vehicle. This requires developing price competitive connector which has enough elastic design to be able to withstand assembly and vehicle operating conditions. The tight and non-flexible connector may not be enough to withstand vibrations, thermal contraction or expansion of the whole module, and in particular may not be suitable to transfer supercritical fluids.
The prior art solutions concern rubber hose part crimped to metal pipes what allows to compensate tolerances and withstand vibration stress (see Fig.2). In case of module application, distance between two gas coolers is very small what creates problems with limited bending radius for rubber part, and thus elastic rubber hose is not compact enough.
Moreover, the rubber hose has poor reliability (it's not robust enough) what may lead to potential leaks of high pressure refrigerant. On top of that complex design of the elastic connector with rubber hose has as significantly higher price.
One of the way to provide cheaper connector is to provide a simple, metallic U-shaped pipe which will connect the heat exchangers of the assembly (see Fig.3).
However, this may create another problem associated with lack of elasticity of the connector.
Therefore, there is a need to increase reliability of the connector so that the high pressure fluids may circulate in the assembly.
Further, there is a need to provide cheap and simple connector, which will withstand the mechanical requirements.
Further, there is a need to provide more flexible connection between the heat exchangers which be able to compensate tolerances.
Further, the is a need to provide more flexible connection between the heat exchangers which will be resistant to vibrations.
Further, there is a need to provide an assembly which will decrease carbon footprint of the vehicle which carries such assembly.

SUMMARY OF THE INVENTION

The object of the invention is, inter alia, a heat exchanger assembly for heat exchange between a first fluid and at least a second fluid comprising: a first heat exchanger configured for flow of a first fluid therein, and a second heat exchanger, the heat exchanger assembly further comprising a substantially helical portion, the helical portion being configured to provide a fluidal communication between the first heat exchanger and the second heat exchanger.
Advantageously, the helical portion comprises a conduit, the conduit comprising a circular cross-section along entire intended first fluid flow path between the first heat exchanger and the second heat exchanger.
Advantageously, the helical portion comprises a first diameter and the second diameter, the first diameter being a distance measured between the inner walls of the conduit, and the second diameter being the distance measured between the outer walls of the conduit.
Advantageously, the helical portion is smooth space curve with tangent lines at a constant angle to a fixed axis, so that it forms a loop.
Advantageously, the helical portion comprises at least a primary loop and a secondary loop, wherein the loops are arranged next to each other.
Advantageously, the distance between the consecutive loops, is smaller than the second diameter.
Advantageously, the helical portion further comprises at least one straight section located at the opposite sides of the helical portion, the straight section being configured to facilitate connection between the heat exchangers.
Advantageously, the helical portion further comprises at least one meandering portion, the meandering portion protruding directly form the straight section, wherein the meandering portion further comprises a first bend and a second bend.
Advantageously, one open end of the helical portion is fixed directly to a first block, the first block being located between the first heat exchanger and the helical portion.
Advantageously, the other open end of the helical portion is fixed directly to a second block, the second block being located between the second heat exchanger and the helical portion.
Advantageously, the second block is at the different level than the first block.
Advantageously, the helical portion is made of metallic material, so that the assembly is configured to withstand the pressure of the first fluid of at least 180 bar.
Advantageously, the first heat exchanger comprises a first manifold and a second manifold spaced apart from the first manifold , wherein the second manifold is substantially parallel with respect to the first manifold, a plurality of flat tubes stacked between the first manifold and the second manifold , the plurality of flat tubes being configured to provide the fluidal communication between the first manifold and the second manifold , and wherein the second heat exchanger comprises a third manifold and a fourth manifold spaced apart from the third manifold , wherein the fourth manifold is substantially parallel with respect to the third manifold , a plurality of flat tubes stacked between the third manifold and the fourth manifold , the plurality of flat tubes being configured to provide the fluidal communication between the third manifold and the fourth manifold , wherein at least one of the heat exchangers , is a gas cooler.
Advantageously, the heat exchanger assembly further comprises at least a third heat exchanger for a heat exchanger between the first fluid and a third fluid, wherein the third heat exchanger is arranged between the first heat exchanger and the second heat exchanger.
Advantageously, at least the third heat exchanger comprises a first inlet for the ingress of the third fluid therein, and at least one outlet for the egress of the third fluid therefrom, wherein the helical portion surrounds at least the first inlet.
The invention shortly described above provides a compact design, improved elasticity comparing to prior art, what leads to the fact that it is able to withstand difficult conditions (i.e. it's durable).
Moreover, the proposed invention allows providing and assembly with significantly lower price compared to prior art solutions with connectors having rubber elastic structure. The invention also allows to provide cheap connection thanks to lack of additional elements like rubber pipe and crimping areas between rubber and metal pipe.
The proposed invention is environmentally friendly due to simple design without risk of leak for example form crimping area between rubber and metal pipes. In general, the reliability is significantly increased.
Furthermore, the invention allows to reduce time required for production of process due to simplicity of design and lack of additional elements like those that rubber pipe means. Consequently, lower energy consumption leads to better environmental impact mitigation.
Finally, the invention is applicable in vehicles of all types, including ones in which operation of refrigerant loop is under high pressure (>180 bar) due to increased robustness comparing to prior art solutions.

BRIEF DESCRITPTION OF DRAWINGS

Examples of the invention will be apparent from and described in detail with reference to the accompanying drawings, in which:

Fig. 1 shows a perspective view of the heat exchanger assembly having three heat exchangers arranged in sequence, one downstream the other.
Fig. 2 shows an exemplary elastic hose according to the prior art.
Fig. 3 shows an exemplary metallic U-shaped connector according to the prior art.
Fig. 4 shows a side view of heat exchanger assembly having two heat exchangers connected by helical portion according to the embodiment of the invention.
Fig. 5 shows a side view of the helical portion and the detailed view of its cross section A-A'.
Fig. 6 shows another side view of the helical portion comprising connectors on both ends.
Fig. 7 shows the back view helical portion comprising straight sections.
Fig.8 the perspective view of the helical portion of Fig.7.
Fig. 9 shows a back view of helical portion of Fig. 6.
Fig. 10 shows a perspective view of the helical portion of Figs 6-7, showing the location of the straight portions and meandering portions of the helical portion.

DETAILED DESCRIPTION OF EMBODIMENTS

The subject-matter of the invention is, among others, a heat exchanger assembly 1000 (hereinafter referred to as "assembly") for heat exchange between a first fluid and at least a second fluid. The first fluid may be, for example air and the second fluid may be, for example, refrigerant. Preferably, the second fluid is high-pressure refrigerant such as supercritical carbon-dioxide (R744) or high-pressure propane (R290). The type of the first fluid and the second fluid may be selected depending on the application. The assembly 1000 may further comprise a first heat exchanger 100 configured for flow of a second fluid therein and a second heat exchanger 200. The assembly 1000 is hereafter described as the assembly of two air gas coolers, so that the first heat exchanger 100 is a first air gas cooler, and the second heat exchanger 200 is a second air gas cooler arranged downstream to the first air gas cooler, with respect to the intended first fluid (i.e. air) direction. This arrangement is shown for example in Fig. 1 and in Fig. 4. The other types of the heat exchangers 100, 200 are also envisaged. For instance, the first heat exchanger 100 may be a water condenser, whereas the second heat exchanger 200 may be, for example, a chiller. Plenty of applications are possible as thanks to the fact that the heat exchanger assembly 1000 further comprises a substantially helical portion 500. The term substantially indicates that any element being in shape of helix, coil-like or spring-like is also envisaged.
The prior art connectors 901, 902 are shown in Figs 2 and 3.
Referring to Fig. 1 and Fig. 4, the helical portion 500 is configured to provide a fluidal communication between the first heat exchanger 100 and the second heat exchanger 200. Each of the first heat exchanger 100 and the second heat exchanger 200 may comprise an inlet for the second fluid and an outlet for the second fluid. The helical portion 500 may thus connect the outlet of the first heat exchanger 100 with the inlet of the second heat exchanger 200 or vice-versa; the helical portion may connect the outlet of the second heat exchanger 200 with the inlet of the first heat exchanger 100.
In order to provide a desired flow in the helical portion 500, it may further comprise a conduit 501. The conduit 501 may be regarded as the part of the helical portion 500 which determines the flow direction of the fluid onside said helical portion 500. The conduit 501 may comprise a circular cross-section along entire intended second fluid flow path between the first heat exchanger 100 and the second heat exchanger 200. The circular cross-section is proven to be effective not only in fluid dynamics, but it also allows providing a robust channel for the second fluid, so that the second fluid flow direction may be changed according to the needs. As the conduit 501 and the helical portion 500 are preferably made of metal, the formation of the metals apply. It is also envisaged that the helical portion or its conduit could be made of synthetic material, for example by injection molding, but the elasticity or robustness could be seriously reduced.
Referring to Fig. 5, the helical portion 500 may comprise a first diameter D1 and the second diameter D2. The first diameter D1 is a distance measured between the inner walls of the conduit 501. The second diameter D2 being the distance measured between the outer walls of the conduit 501. In case the helical portion 500 comprises the conduit 501 having different cross- section than circular, the first diameter D1 is to be regarded as the hydraulic diameter. D2 may be preferably about 9mm.
Naturally, the thickness of the walls T (not shown) of the conduit 501 in a particular section is the difference between the second diameter D2 and the first diameter D1. The thickness of only one wall of the conduit can be regarded as T/2 (not shown). T/2 may be preferably about 1,5mm.
All of these parameters can be seen in the detailed section of cross-section A-A' in Fig. 5. Further, the helical portion 500 may comprise a first loop 510, wherein D3 is the diameter of the first loop 510. The loop 510 being part of the helical portion 500 can be understood as smooth space curve with tangent lines at a constant angle α to a fixed axis X1. In other words, the loop 510 forms the conduit 501 of the helical portion 500 in such a manner, that in at least one plane the conduit 501 forms the full circle and overlaps at least portion thereof. Said plane is perpendicular to the axis X1. Another loop 510 starts in a place where such overlap is present. Therefore, the loop 510 may comprise at least a primary loop 510A, a secondary loop 510B, etc.
The loops 510A, 510B may be arranged next to each other, as shown in Figs 7-10. It provides a positive effect of reduced packaging of the helical portion 500. Nevertheless, it is preferred that the consecutive loops 510A, 510B are devoid of contact, due to the fact that the vibration caused by the array 1000 in operation may damage the outer surface of the conduit 501. It is preferred that the distance between the consecutive loops 510a, 510B is smaller than the second diameter D2. It allows to provide save distance and enhances flexibility of the helical portion 500. Another way of providing contact between the consecutive loops 510A, 510B is also envisaged: in case the first loop 510A has one diameter D3, and the second loop 510B has another diameter D3' (not shown), wherein the diameter D3' is, for example, smaller that the diameter D3, the two loops 510, 520 can remain at the safe distance with respect to each other.
In order to facilitate connection of the helical portion 500 to the heat exchangers 100, 200, the helical portion 500 may further comprise at least one straight section 530, as shown for example in Fig. 7. Preferably, there are two straight sections 530 located at the opposite sides of the helical portion 500. The assembly 1000 may also comprise the connecting blocks. For example, the one end of the helical portion 500 may be fixed directly to a first block 610. The first block 610 may be located between the first heat exchanger 100 and the helical portion 500. This provides a fluid-tight connection and facilitates connection of the helical portion 500 to the heat exchanger.
Similarly, the other open end of the helical portion 500 may be fixed directly to a second block 620. The second block 620 may be located between the second heat exchanger 200 and the helical portion 500.
As shown in Fig. 7, the straight sections 530 of the helical portion 500 set the blocks 610, 620 spaced apart in relation to axis X1. This can be compensated, and the blocks 610, 620 may be brought closer to each- other, if needed. In order to change the location of the blocks 610, 620 in reference to the axis X1, the helical portion 500 may further comprise at least one meandering portion 550, as shown in Fig. 9 and Fig. 10. Term meandering means two consecutive turns, preferably at the same rate, so that the intended fluid flow direction is shifted.
The meandering portion 550 may protrude directly form the straight section 530 or directly from the end of the loops 510A, 510B, if needed.
The meandering portion 550 further comprises a first bend 550A and a second bend 550B. The first bend 550A is for shifting the open ends conduit 501 inwardly, i.e. towards each other. The second bend 550B is for straightening the path of fluid, so that the open ends of the helical portion 500 are facing the same direction, as if the bends 550A, 550B did not exist. Both the bends 550A, 550B have a radius which is smaller than 90 degrees. In other words, the aim of the bends 550A, 550B is to slightly deflect the path of the conduit 501, not providing any U-turns.
Accordingly, in case the one end of the helical portion 500 comprises the straight section 530 and the other does not, or in case where one straight section 530 is longer than the other straight section 530 located at the opposite end of the helical portion 500, the second block 620 may at the different level than the first block 610. The embodiment where the blocs 610, 620 are at the same level is also envisaged.
The level can be defined as horizontal plane or line with respect to the distance above or below a given point, such as ground level.
It should be noted that when assembled, the entire array 1000 may be inclined (for example when mounted onto the vehicle). Such inclination may also set the second block 620 at the different level than the first block 610.
The helical portion 500 is preferably made of metallic material such as aluminum, so that the assembly 1000 is configured to withstand the pressure of the second fluid of at least 180 bar. As already discussed, the helical portion 500 may be also made of other materials, but they may bring many drawbacks, such as lack of rigidity or elasticity. Therefore it is not advised to use the materials other than metallic, unless they bring all effects of the present invention.
The array 1000 may comprise different setups, i.e. the helical portion 500 may fludically connect various types of heat exchangers 100, 200.
The invention is mainly shown in a setup of the first heat exchanger 100 being one gas cooler, the second heat exchanger 200 being the second gas cooler fluidly connected to the first heat exchanger 100 by the helical portion 500, wherein the heat exchangers 100, 200 are so spaced apart from each- other, that they can accommodate the third heat exchanger 300, in this case low temperature radiator, in-between them, as shown for example in Fig.1.
Referring back to Fig. 1, all three heat exchangers 100, 200, 300 are arranged sequentially to allow the first fluid, i.e. to flow across their surfaces.
The first heat exchanger 100 may a first manifold 110 and a second manifold 120 spaced apart from the first manifold 110. The second manifold 120 may be substantially parallel with respect to the first manifold 110. Substantially parallel means that there may be some deviations from the ideally-parallel configuration (i.e. technological tolerances).
The first heat exchanger 100 may further comprise a plurality of flat tubes 150 stacked between the first manifold 110 and the second manifold 120. The tubes 150 are stacked in the first stacking direction which is substantially parallel to the main axis of extension of the manifolds 110, 120. The plurality of flat tubes 150 may be configured to provide the fluidal communication between the first manifold 110 and the second manifold 120. For example, the Tubes 150 may be extruded tubes to withstand the high-pressure of the second fluid flowing therein.
Analogically, the second heat exchanger 200 may comprise a third manifold 210 and a fourth manifold 220 spaced apart from the third manifold 210 The fourth manifold 220 may be substantially parallel with respect to the third manifold 210. The second heat exchanger 200 may further comprise a plurality of flat tubes 250 stacked between the third manifold 210 and the fourth manifold 220. The plurality of flat tubes 250 may be configured to provide the fluidal communication between the third manifold 210 and the fourth manifold 220.
The heat exchanger assembly 1000 further comprising at least a third heat exchanger 300, wherein the third heat exchanger 300 is arranged between the first heat exchanger 100 and the second heat exchanger 200. The third heat exchanger 300 may be fluidly connected to different loop than the first heat exchanger 100 and the second heat exchanger 200. For instance, the third heat exchanger may be for heat exchange of the third fluid, such as coolant, with the first fluid, i.e. the same air with which the first heat exchanger 100 and the second heat exchanger 200 exchange calories.
The third heat exchanger 300 may comprise a first inlet 301 for the ingress of the third fluid therein, and at least one outlet 302 for the egress of the third fluid therefrom. In order to provide the extreme level of packaging, the helical portion 500 may be so configured that it surrounds at least the first inlet 301. In this case, diameter of the first loop 510 must be greater than the outline of said inlet 301. Naturally, the helical portion 500 may be so configured that it surrounds at least the first outlet 302. In this case, diameter of the first loop 510 must be greater than the outline of said outlet 302.
Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of drawings, the disclosure, and the appended claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to the advantage.

Claims

A heat exchanger assembly (1000) for heat exchange between a first fluid and at least a second fluid comprising: a first heat exchanger (100) configured for flow of a second fluid therein, and a second heat exchanger (200), the heat exchanger assembly (1000) further comprising a substantially helical portion (500), the helical portion (500) being configured to provide a fluidal communication between the first heat exchanger (100) and the second heat exchanger (200).
The heat exchanger assembly (1000) according to claim 1, wherein the helical portion (500) comprises a conduit (501), the conduit (501) comprising a circular cross-section along entire intended second fluid flow path between the first heat exchanger (100) and the second heat exchanger (200).
The heat exchanger assembly (1000) according to claim 2, wherein the helical portion (500) comprises a first diameter (D1) and the second diameter (D2), the first diameter (D1) being a distance measured between the inner walls of the conduit (501), and the second diameter (D2) being the distance measured between the outer walls of the conduit (501).
The heat exchanger assembly (1000) according to any of the preceding claims, wherein the helical portion (500) is smooth space curve with tangent lines at a constant angle (α) to a fixed axis (X1), so that it forms a loop (510).
The heat exchanger assembly (1000) according to any of the preceding claims, wherein the helical portion (500) comprises at least a primary loop (510A) and a secondary loop (510B), wherein the loops (510A, 510B) are arranged next to each other.
The heat exchanger assembly (1000) according to claims 3 and 5, wherein the distance between the consecutive loops (510, 520) is smaller than the second diameter (D2).
The heat exchanger assembly (1000) according to any of the preceding claims, wherein the helical portion (500) further comprises at least one straight section (530) located at the opposite sides of the helical portion (500), the straight section (530) being configured to facilitate connection between the heat exchangers (100, 200).
The heat exchanger assembly (1000) according to claim 7, wherein the helical portion (500) further comprises at least one meandering portion (550), the meandering portion (550) protruding directly form the straight section (540), wherein the meandering portion (550) further comprises a first bend (550A) and a second bend (550B).
The heat exchanger assembly (1000) according to any of the preceding claims, wherein one open end of the helical portion (500) is fixed directly to a first block (610), the first block (610) being located between the first heat exchanger (100) and the helical portion (500).
The heat exchanger assembly (1000) according to claim 9, wherein the other open end of the helical portion (500) is fixed directly to a second block (620), the second block (620) being located between the second heat exchanger (200) and the helical portion (500).
The heat exchanger assembly (1000) according to claim 10, wherein the second block (620) is at the different level than the first block (610).
The heat exchanger assembly (1000) according to any of the preceding claims, wherein the helical portion (500) is made of metallic material, so that the assembly (1000) is configured to withstand the pressure of the second fluid of at least 180 bar.
The heat exchanger assembly (1000) according to any of the preceding claims, wherein the first heat exchanger (100) comprises a first manifold (110) and a second manifold (120) spaced apart from the first manifold (110), wherein the second manifold (120) is substantially parallel with respect to the first manifold(110), a plurality of flat tubes (150) stacked between the first manifold (110) and the second manifold (120), the plurality of flat tubes (150) being configured to provide the fluidal communication between the first manifold (110) and the second manifold (120), and wherein the second heat exchanger (200) comprises a third manifold (210) and a fourth manifold (220) spaced apart from the third manifold (210), wherein the fourth manifold (220) is substantially parallel with respect to the third manifold (210), a plurality of flat tubes (250) stacked between the third manifold (210) and the fourth manifold (220), the plurality of flat tubes (250) being configured to provide the fluidal communication between the third manifold (210) and the fourth manifold (220), wherein at least one of the heat exchangers (100, 200) is a gas cooler.
The heat exchanger assembly (1000) further comprising at least a third heat exchanger (300) for a heat exchanger between the first fluid and a third fluid, wherein the third heat exchanger (300) is arranged between the first heat exchanger (100) and the second heat exchanger (200).
The heat exchanger assembly (1000) according to claim 15, wherein at least the third heat exchanger (100) comprises a first inlet (301) for the ingress of the third fluid therein, and at least one outlet (102) for the egress of the third fluid therefrom, wherein the helical portion (500) surrounds at least the first inlet (101).