HEAT EXCHANGER FOR AN ELECTRICAL AND / OR ELECTRONIC COMPONENT OF A MOTOR VEHICLE

Description

[0001] The field of the present invention relates to the thermal regulation of an electrical and / or electronic element, and more particularly, the present invention relates to an exchanger for the thermal regulation of an electrical and / or electronic element intended for electric or hybrid motor vehicles.

[0002] Electrical and / or electronic components can include, for example, batteries, power electronic devices, or computer servers.

[0003] Electric and hybrid vehicles are commonly equipped with a battery. Such an electrical and / or electronic component consists of an assembly of electrical modules, themselves made up of an assembly of electrochemical cells.

[0004] To ensure the autonomy, performance, and reliability of such an electrical and / or electronic component, it is generally necessary to regulate its temperature. Thermal management of the electrical and / or electronic component aims to maintain the temperature of its constituent electrical modules at a temperature approximately between 20°C and 40°C. Indeed, when the temperature of an electrical module is too low, the capacity of its electrochemical cells decreases, and when the temperature of an electrical module is too high, the lifespan of its electrochemical cells is reduced. To achieve this thermal management, it is known to use a thermal management device comprising at least one heat exchanger in direct contact with an electrical module of the electrical and / or electronic component and through which a heat transfer fluid flows.In order for the heat transfer fluid to circulate, the heat exchanger(s) are traversed by a heat exchange circuit formed for example by ducts provided in the heat exchanger(s) themselves.

[0005] Electrical and / or electronic components, whether electrical energy storage cells, integrated circuits, servers, data centers, etc., require thermal regulation to maintain them within their operating temperature range.

[0006] The invention is in particular intended to equip motor vehicles, especially electric or hybrid motor vehicles, and to thermally regulate an electrical energy storage cell or power electronics elements.

[0007] With the market share of electric vehicles steadily increasing, the dielectric and heating issues of the battery packs they use are becoming strategic priorities. The objective is to design the most efficient, effective, and economical battery thermal management system possible. A heat exchanger according to the preamble of claim 1 is known from US patent 2010 / 044019 A1.

[0008] A typical problem with these heat exchangers is the uneven heat dissipation along their length. The heat transfer fluid flowing through the exchanger heats up throughout the channel due to the absorption of heat from the electrical and / or electronic component being cooled. The same occurs when the fluid is used to heat the electrical and / or electronic component; the fluid cools upon contact with the component. Therefore, the heat exchange capacity between the inlet and outlet of a heat exchanger differs, and the cooling or heating of the electrical and / or electronic component is degraded.

[0009] As a general rule, in the field of electric batteries for example, a temperature difference of no more than 10 degrees Celsius should not be observed between the first and last cell of an electric battery module in order to optimize their operation, it is therefore necessary to be able to ensure a small temperature difference between the part of the element or the element near the inlet of the heat transfer fluid and the part of the element or the element near the outlet of the heat transfer fluid.

[0010] One of the aims of the present invention is to remedy at least partially the disadvantages of the prior art and to propose a heat exchanger that limits the impact of the temperature difference of the heat transfer fluid observed between the inlet and outlet of the heat exchanger on the thermal management of an electrical and / or electronic element.

[0011] The invention applies in particular to a circulation within an "I-type" exchanger or to a plurality of loops connected in parallel within the same exchanger.

[0012] The present invention therefore relates to a heat exchanger for the thermal management of an electrical and / or electronic component, advantageously of a vehicle, comprising a heat exchange body having: a heat exchange surface intended to be in thermal contact with the electrical and / or electronic element, a base surface opposite the heat exchange surface, a flow channel for a heat transfer fluid formed between the heat exchange surface and the base surface, the drainage channel comprising: a first zone presenting a first means of perturbing the flow of heat transfer fluid, a second zone presenting a second means of perturbing the flow of heat transfer fluid, the first means of flux perturbation consisting of a plurality of local deformation of the base surface and the second means of flux perturbation consisting of a fin arranged between the heat exchange surface and the base surface and forming a plurality of flow paths.

[0013] The invention provides a heat exchanger comprising zones with different heat transfer coefficients. This allows for more homogeneous heat treatment of the electrical and / or electronic component(s) by mitigating the impact of the heat transfer fluid temperature. Specifically, by increasing the flow disturbance and the exchange surface area with the fluid, the fin in the second zone of the flow channel significantly increases the heat transfer coefficient of this second zone compared to that of the first zone.

[0014] Advantageously, the heat exchange wall is flat so as to provide a heat exchange surface allowing good thermal contact with the electrical and / or electronic element to be thermally regulated.

[0015] The heat exchange wall is intended to be in thermal contact with, or in view of, an element to be thermally regulated.

[0016] The heat transfer fluid intended to circulate in the heat exchanger can be a refrigerant (1234YF, 134a or R744 for example) or a coolant (for example glycol water).

[0017] The average hydraulic diameter is understood to be the average hydraulic diameter over the entire length of the flow channel in an area.

[0018] The invention may also include any of the additional features listed below, taken alone or in combination with each other as long as they are technically compatible: The second flow disturbance means is capable of generating greater turbulence in the heat transfer fluid flow than the turbulence generated by the first flow disturbance means, thus the second zone has a higher heat transfer coefficient than the first zone; the first zone has a first average hydraulic diameter and the second zone has a second average hydraulic diameter; the first and second zones have the same average hydraulic diameter; the second average hydraulic diameter is greater than the first average hydraulic diameter. The average hydraulic diameter is understood to be the average of the hydraulic diameter over the entire length of the flow channel of a zone;

[0019] Thus, by combining the increase in hydraulic diameter and the increase in flow disturbance generated by the flow disturbance means, it is possible to increase the heat exchange coefficient of the second zone compared to the first zone and thus limit the impact of the increase in the temperature of the heat transfer fluid on the temperature of the electrical and / or electrical element to be thermally regulated. the base wall comprises, at the level of the first zone of the flow channel, local deformations, or protrusions, and undeformed parts, the ratio of deformations / undeformed parts per cm² of the first zone is constant over the whole of the first zone, the base wall comprises, at the level of the first zone of the flow channel, local deformations, or protrusions, and undeformed parts, the ratio of deformations / undeformed parts per cm² of the first zone is evolving, advantageously it is increasing throughout the first zone; each deformation has a height H extending between the undeformed parts of the base wall and a top, advantageously the top being away by a non-zero distance d from the heat exchange wall;In other words, the height H of the deformation is strictly less than the height of the channel. Since the distance d is identical for all deformations within the same zone, if the height Hc of the channel increases, the height H of the protrusion increases identically so as to maintain the same distance d between the top of the protrusions and the heat exchange wall; the height H of the deformations being identical for all deformations within the same zone; the fin can be of the "staggered pitch," louvered, straight, or corrugated type; the first and second zones are directly contiguous, or separated by a transition zone; advantageously, when the flow disturbance means is a fin, the hydraulic diameter is constant over the entirety of the same zone; the flow channel extends between a fluid inlet and outlet;the heat exchange body has a plurality of flow channels, each channel comprising its own inlet and outlet or at least a plurality of channels share a common inlet and outlet, for example in communication with a supply chamber feeding the channels and an outlet chamber, evacuating the fluid towards the outlet; the heat exchange wall is a first plate and the base wall is a second plate, the channel being formed by at least one deformation of the second plate, thus providing a space between the heat exchange wall and the base wall, the space forming the flow channel;The deformations of the first zone consist of local deformations of the portion of the base wall forming the channel. In other words, the deformations of the first zone consist of deformations of a general pattern of the base wall at the level of the first zone of the channel. The fin is assembled between the first and second plates; the heat exchanger is made of metal, advantageously aluminum, and assembled, for example, by laser welding or brazing; the increase in hydraulic diameter along the channel is continuous; in order to increase the hydraulic diameter, the height and / or width of the channel is increased; the hydraulic diameter of the first and second zones is different, advantageously the hydraulic diameter is constant along each zone, and the first and second zones are separated from each other by a transition zone;the first zone extends between 50 and 80% of the total length of the channel, advantageously around 70%. the first zone of the flow channel comprises a fluid inlet, a feed chamber and a plurality of pipes, the feed chamber supplying the plurality of pipes, according to a first embodiment, each pipe opens directly into the second zone, according to another embodiment, each pipe opens into the transition zone;The flow channel extends between a fluid inlet and outlet; advantageously, the first zone is on the inlet side and the second zone on the outlet side in the case of a heat exchanger for cooling an electrical and / or electronic component, and for a heat exchanger used in heating an electrical and / or electronic component, the first zone is located on the outlet side and the second zone on the inlet side. The heat exchange body comprises a supply line, feeding a plurality of flow channels, and a discharge line removing the fluid from the flow channels, each flow channel being connected to the supply line by its inlet, and to the discharge line by its outlet.

[0020] The invention also relates to a housing comprising a plurality of walls forming an internal compartment and a heat exchanger as described above, advantageously assembled within the internal compartment. Advantageously, the housing includes an electrical and / or electronic element assembled in thermal contact with the heat exchanger.

[0021] It goes without saying that the characteristics described in relation to the different modes of implementation can be combined as long as there is no technical or structural contradiction to being combined.

[0022] Other features and advantages of the invention will become clearer upon reading the following description, given by way of illustrative and non-limiting example, and the accompanying drawings, among which: There figure 1 shows a schematic representation of the heat exchanger according to a first embodiment of the invention, The figure 2 shows a side view of a third embodiment of the invention. The figure 3 shows a cross-sectional view of the heat exchanger figure 1 according to a cutting plan AA'. The figure 4 shows a cross-sectional view of the heat exchanger figure 1 according to a cutting plan BB'.

[0023] In the different figures, identical elements bear the same reference numbers.

[0024] The following are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to a single embodiment. Simple features from different embodiments can also be combined to provide other embodiments.

[0025] In this description, certain elements or parameters can be indexed, such as "first zone" or "second zone," "first parameter" and "second parameter," or "first criterion" and "second criterion," etc. In this case, it is simply indexing to differentiate and name similar but not identical elements, parameters, or criteria. This indexing does not imply any priority of one element, parameter, or criterion over another, and such designations can easily be interchanged without departing from the scope of this description. Nor does this indexing imply any order in time, for example, for evaluating one criterion over another.

[0026] There figure 1 being a view from below, only the base wall is visible, the heat exchange wall being opposite the base wall will not be shown in this figure.

[0027] There figure 1 represents a first embodiment of the invention in which the heat exchanger 1 comprises a heat exchange body 2 having: a heat exchange wall 3 (not shown in this figure) intended to be in thermal contact with the electrical and / or electronic element, a base wall 4 opposite the heat exchange wall, a flow channel 5 for a heat transfer fluid formed between the heat exchange wall and the base wall, the drainage channel comprising: a first zone 51 presenting a first means of perturbing the flow of heat transfer fluid 61, a second zone presenting a second means of perturbing the flow of heat transfer fluid 62, the first means of flux perturbation 61 consisting of a plurality of local deformations of the base surface and the second means of flux perturbation 62 consisting of a fin arranged between the exchange surface thermal and the base surface and forming a plurality of flow paths.

[0028] The heat exchange body 2 comprises a plurality of flow channels 5, each extending between an inlet 7 and an outlet 8. Each flow channel 5 thus comprises an inlet 7, a supply chamber 71, two conduits 511, a discharge chamber 81, and an outlet 8. Each of these channels is connected by its inlet 7 to a supply conduit 9 and by its outlet to a discharge conduit 10. The supply conduit comprises a supply opening 11, and the discharge conduit comprises a discharge opening 12, the openings 11 and 12 being intended to be connected to a heat transfer fluid circulation circuit. Each embodiment may comprise a supply conduit and a discharge conduit as shown in the figure 1 .

[0029] The flow channel 5 has, along the first zone 51, two parallel and sealed conduits 511. The heat exchange body 2 includes a separator 21 for separating the conduits 511 from each other. The conduits 511 open into the second zone 52 of the flow channel 5.

[0030] There figure 2 presents an embodiment in which the hydraulic diameter is constant along each zone 51, 52, the second hydraulic diameter being greater than the first hydraulic diameter and the first 51 and second 52 zones are separated from each other by a transition zone 54. The transition zone 54 being a zone of hydraulic diameter evolving in the direction of flow passing from the first hydraulic diameter to the second hydraulic diameter.

[0031] There figure 3 represents the exchanger of the figure 1 according to a cutting plan AA'.

[0032] The first zone 51 comprises two pipes 511 sealed from each other and separated by a separator 21. According to one embodiment, the separator is a sealed contact zone between a plate forming the base wall 4 and a plate forming the heat exchange wall 3.

[0033] Each deformation 61 has a height H extending between the undeformed parts 41 of the base wall and a vertex 611 of the deformation 61, advantageously the vertex 611 being located a non-zero distance d away from the heat exchange wall 3; The figure 4 represents a cross-sectional view of a heat exchanger according to the embodiment of the figure 1 according to a cutting plan BB'.

[0034] There figure 4shows particularly the interior of the flow channel 5 at the level of the second zone 52. The flow channel 5 includes a fin 62 between the base wall 4 and the heat exchange wall 3. The fin 62 is assembled between a plate forming the heat exchange wall 3 and a plate forming the base wall 4.

Claims

1. Heat exchanger, comprising a heat exchange body having: - a heat exchange surface - a base surface opposite to the heat exchange surface, - a flow channel of a heat transfer fluid formed between the heat exchange surface and the base surface, the flow channel comprising: - a first zone having a first means for disturbing the heat transfer fluid flow, - a second zone having a second means for disturbing the heat transfer fluid flow, the first flow disturbance means consisting of a plurality of local deformations of the base surface and the second flow disturbance means consisting of a fin arranged between the heat exchange surface and the base surface and forming a plurality of flow paths, so as to significantly increase the heat transfer coefficient of the second zone compared to the heat transfer coefficient of the first zone of the flow channel, and characterized in that the flow channel (5) comprises a plurality of conduits (511) parallel to each other at the first zone (51) and in that the heat exchanger is for thermal management of an electrical and / or electronic element advantageously of a vehicle and in that the heat exchange surface is intended to be in thermal contact with the electrical and / or electronic element.

2. Heat exchanger according to the preceding claim, wherein the second flow disturbance means (62) is capable of generating a turbulence of the heat transfer fluid flow higher than the turbulence generated by the first flow disturbance means (61) and / or the second average hydraulic diameter is greater than the first average hydraulic diameter.

3. Heat exchanger according to the preceding claim, wherein the base wall comprises the deformations and non-deformed parts between each deformation, the ratio of deformations / non-deformed parts per cm2 of the first zone can be constant or evolving along the first zone.

4. Heat exchanger according to one of the preceding claims, wherein each deformation has a height H and a summit distant by a non-zero distance d from the heat exchange wall.

5. Heat exchanger according to one of the preceding claims, wherein the heat exchange wall (3) is a first plate and the base wall (4) is a second plate, the flow channel (5) being formed by at least one deformation of the second plate.

6. Heat exchanger according to one of the preceding claims, wherein the hydraulic diameter increases regularly along the first zone of the channel and / or or the second zone (52).

7. Heat exchanger according to one of claims 1 to 5 wherein the hydraulic diameter is constant along each zone (51, 52), and the first (51) and second zones (52) are separated from each other by a transition zone (53)8. Heat exchanger according to one of the preceding claims, wherein the first zone extends between 50 and 80% of the total length of the channel, advantageously 70%.

9. Housing comprising a plurality of walls forming an internal compartment and a heat exchanger according to one of the preceding claims, advantageously the heat exchanger being positioned within the internal compartment.