FR3126767A1 - HEAT EXCHANGER OF A REFRIGERANT LOOP. - Google Patents

Abstract

Heat exchanger of a refrigerant loop. The invention relates to a heat exchanger (2) for a refrigerant loop of a vehicle, comprising a heat exchange surface (12) comprising a plurality of tubes (20) configured to channel the refrigerant, the heat exchanger (2) comprising at least a first refrigerant circuit (24) consisting of a first part (28a) of the plurality of tubes (20), a first inlet chamber (16a) and a first outlet chamber (18a), the heat exchanger (2) comprising at least a second refrigerant fluid circuit (26) consisting of a second part (28b) of the plurality of tubes (20), a second inlet chamber (16b) and a second outlet chamber (18b), at least one of the first circuit (24) and/or of the second circuit (26) being configured to form in the exchange surface (12 ) at least two coolant circulation passes (50) between the inlet chamber (16) and the outlet chamber (18) of said circuit. Fig.5

Description

Heat exchanger of a refrigerant loop.

The present invention relates to a refrigerant fluid loop intended for the circulation of a refrigerant fluid and applied to a heating, ventilation and/or air conditioning installation for a motor vehicle, and more particularly for electric cars or hybrid cars.

An electric or hybrid car has a refrigerant fluid loop in order to vary the temperature inside its passenger compartment, and in particular to heat it in winter and to cool it in summer. The temperature of the passenger compartment is modified in particular by means of the refrigerant fluid circulating in the refrigerant fluid loop between a heat exchange device arranged in the vehicle in the vicinity of the passenger compartment, and a heat exchanger located in contact with the ambient air, in front of the vehicle. Thus, the coolant circulating in the coolant loop absorbs or releases calories at the heat exchanger or the heat exchange device depending on the heating or cooling needs of the passenger compartment. The use of a compressor and, where appropriate, of an expansion valve is in particular necessary to modify the pressure of the refrigerant fluid in the refrigerant fluid loop in order to thermodynamically modify the temperature of the refrigerant fluid subsequently caused to pass through the device. heat exchanger and heat exchanger.

The heat exchanger located on the front of the vehicle enables the exchange of calories between the coolant which circulates in tubes arranged one above the other and spaced from one another by spacers, and an air flow, coming from from outside the vehicle and passing through said heat exchanger between the tubes at the spacers.

In electric or hybrid vehicles, it is known to configure the refrigerant loop and the heat exchanger on the front face to form a reversible heat pump in which the heat exchanger is able to operate in condenser mode, in summer, to ensure the cooling of the passenger compartment via the heat exchange device forming an evaporator in the heating, ventilation and/or air conditioning installation, and to operate in evaporator mode, in winter, to ensure heating in the passenger compartment via the heat exchange device forming a condenser.

A problem with such a heat exchanger placed on the front of the vehicle then lies in its operation as an evaporator, when the temperature differential tends to heat the flow of humid air and create droplets of condensation which are deposited on the surface of the heat exchanger. 'heat exchanger. If the temperature of the refrigerant circulating in the tubes is too low, and the spacers between the tubes are too cold by thermal conduction, the cooling of the condensation droplets may form frost locally on the spacers between the heat exchanger tubes. heat. Such presence of frost generates obstacles to the passage of air through the heat exchanger and therefore tends to reduce the thermal capacities of the heat exchanger.

The present invention aims to remedy this drawback, by proposing a refrigerant loop, and more particularly a heat exchanger, making it possible to limit the formation of frost on the latter. The invention therefore makes it possible to increase the thermal capacities of the heat exchanger and therefore of the refrigerant fluid loop.

The invention therefore relates to a heat exchanger for a refrigerant loop, comprising a heat exchange surface, the heat exchange surface comprising a plurality of tubes, the heat exchanger being characterized in that it comprises at least a first refrigerant circuit consisting of a first part of the plurality of tubes, a first inlet chamber fluidically connected to tubes of the first part of the plurality of tubes and a first chamber outlet fluidly connected to tubes of the first part of the plurality of tubes, the heat exchanger comprising at least a second refrigerant fluid circuit consisting of a second part of the plurality of tubes, a second inlet fluidly connected to tubes of the second part of the plurality of tubes and a second outlet chamber fluidly connected to tubes of the second part of the plurality of tubes, the first part of the plurality of tubes and the second part of the plurality of tubes being fluidly distinct from each other and at least one of the first circuit and/or of the second circuit being configured to form in the exchange surface at least two coolant fluid circulation passes between the chamber input and the output chamber of said circuit.

The refrigerant fluid loop can be arranged within a vehicle, for example electric or hybrid, in order to heat or cool a passenger compartment of said vehicle, in particular via an exchange of calories within the heat exchanger between the refrigerant fluid and an external air flow, the heat exchange surface being intended to be traversed by this external air flow.

The refrigerant fluid loop may consist of a reversible heat pump and the heat exchanger may be an evapo-condenser within which the refrigerant fluid circulates. More specifically, the heat exchanger comprises the heat exchange surface within which heat exchanges take place between the flow of air passing through said exchange surface, and the refrigerant fluid circulating within the plurality of tubes of said exchange surface, the coolant capturing or transferring calories to the air flow depending on the configuration of the coolant loop, intended to heat or cool the passenger compartment.

The tubes are stacked along a stacking direction, with a space left between two neighboring tubes to allow airflow through the heat exchange surface. These tubes are configured to channel the refrigerant fluid along a direction of main elongation of the tubes and they are each fluidly connected to inlet chambers allowing the supply of refrigerant fluid and outlet chambers allowing the evacuation of this coolant.

The first inlet chamber and the second inlet chamber respectively of the first circuit and of the second circuit are fluidly connected to a first portion of the refrigerant fluid loop, said first portion being to be considered as the portion connecting a heat exchanger, which may consist of a condenser or an evaporator depending on the operating configuration of the control loop, to the heat exchanger and borrowed in this direction by the refrigerant fluid. This first portion may in particular comprise at least one compressor or one expansion member. A branch is formed on the first portion of the refrigerant fluid loop and the refrigerant fluid which circulates therein is split into two flows directed respectively towards the first inlet manifold and towards the second inlet manifold.

The first inlet chamber and the second inlet chamber respectively of the first circuit and of the second circuit are fluidically connected to a second portion of the refrigerant fluid loop, the second portion of the refrigerant fluid loop being to be considered as the portion connecting the heat exchanger to the previously mentioned heat exchanger, which may consist of a condenser or an evaporator depending on the operating configuration of the control loop, and borrowed in this direction by the refrigerant fluid. This second portion may in particular comprise at least one compressor or one expansion member. A connection is formed between the two outlet manifolds and the second portion of the refrigerant fluid loop so that the two flows leaving the outlet manifolds converge towards the second portion of the refrigerant fluid loop.

As mentioned, according to the invention, at least one of the first circuit and/or of the second circuit is configured to form at least two refrigerant fluid passes within the exchange surface, one refrigerant fluid pass being defined by the circulation of the coolant in the heat exchange surface in a single direction of circulation. As soon as the heat exchanger is configured at one of its longitudinal ends so that the refrigerant fluid changes direction of circulation within the exchange surface, an additional pass of refrigerant fluid is added. Thus according to the invention, the first circuit can comprise a first pass having a circulation of the refrigerant fluid in a first direction of circulation, from the corresponding inlet chamber of this first circuit, and at least a second pass having a circulation of the fluid refrigerant in a second direction of circulation, opposite to the first direction of circulation, tending to bring the refrigerant fluid closer to the outlet chamber of this first circuit. And the second circuit can comprise a first pass having a circulation of the refrigerant fluid in a first direction of circulation, from the corresponding inlet chamber of this second circuit, and at least a second pass having a circulation of the refrigerant fluid in a second direction of circulation, opposite to the first direction of circulation, tending to bring the refrigerant fluid closer to the outlet chamber of this second circuit.

In this way, it is intended that in at least one zone of the heat exchange surface, one of the tubes of the first circuit and one of the tubes of the second circuit are respectively crossed by the refrigerant fluid with directions of circulation, in a direction of flow going from the inlet to the outlet of each corresponding circuit, which are opposed from one tube to the other.

When the coolant loop is in a configuration where it heats the passenger compartment, the coolant entering the heat exchanger is colder than the flow of air passing through said heat exchanger, said coolant having been expanded by the expansion device upstream of the heat exchanger inlet. Thus, although the flow of air coming from outside the vehicle has a low temperature, it is understood that said flow of air is intended to transfer its calories to the refrigerant in order to heat it. The refrigerant fluid is heated as it circulates through the plurality of tubes, from the inlet manifold to the outlet manifold.

Advantage is then taken of the characteristic of the invention, according to which the first circuit and/or of the second circuit comprises at least two passes, in that this makes it possible to improve the distribution of the temperature on the heat exchange surface. , avoiding large temperature gradients from one end of the heat exchange surface to the other. As mentioned above, it is thus ensured that, in at least one zone of the exchange surface, the circulation of the refrigerant fluid in the first circuit and the circulation of the refrigerant fluid in the second circuit are in opposite directions, allowing a better distribution of the temperature gradient of the coolant in the exchange surface. The temperature of the exchange surface is thus more homogeneous, so that the formation of frost on said exchange surface of the heat exchanger is limited.

According to a characteristic of the invention, within the at least one circuit configured to form at least two coolant circulation passes, the inlet chamber and the outlet chamber are fluidically connected to separate tubes.

According to one characteristic of the invention, within the at least one circuit configured to form at least two coolant fluid circulation passes, a coolant fluid return chamber is fluidly arranged between its inlet chamber and its outlet chamber. exit.

It is understood that the first circuit and/or the second circuit which comprises at least the two passes comprises the return chamber ensuring the passage of the refrigerant fluid from one pass to the other. In other words, the return chamber ensures the fluidic connection between two passes by forcing a change in the direction of circulation of the refrigerant fluid within the exchange surface.

The return chamber is fluidly connected to at least a part of the tubes corresponding to the circuit to which the return chamber is connected, that is to say to tubes of the first part of the plurality of tubes or tubes of the second part of the plurality of tubes depending on the circuit concerned.

According to one characteristic of the invention, within the at least one circuit comprising at least two passes, the return chamber is fluidically connected to all the tubes connected to the inlet chamber and to all the tubes connected to the outlet chamber. In this context, it is understood that the circuit only comprises a return chamber, with the inlet chamber and the outlet chamber which are arranged at the same end of the exchange surface and with the return chamber which is placed at the opposite end.

According to one characteristic of the invention, within the at least one circuit comprising at least two passes, a first chamber for returning the refrigerant fluid is fluidly connected to all the tubes connected to the inlet chamber or to the outlet chamber and a plurality of tubes connected to a second return chamber. In this context, it is understood that the circuit comprises several return chambers, and that at least one and the same end of the exchange surface, a return chamber is arranged in the vicinity of an inlet chamber and/or an output chamber of the corresponding circuit.

According to a feature of the invention, when one of the circuits comprises a single pass, the inlet chamber and the outlet chamber of said circuit are connected to the same tubes.

According to a characteristic of the invention, the first circuit and the second circuit each comprise an identical number of passes.

According to an alternative of the invention, the first circuit and the second circuit each comprise a number of passes different from the number of passes of the other circuit.

According to one characteristic of the invention, at least one of the first circuit and/or of the second circuit comprises a first collector arranged at a first end of the heat exchange surface and a second collector arranged at a second end of the heat exchange surface. heat exchange opposite the first end along the direction of main elongation of the plurality of tubes, the inlet chamber and the outlet chamber of the first circuit and/or the second circuit being arranged in the same first collector or second manifold.

According to an alternative of the invention, at least one of the first circuit and/or of the second circuit comprises a first collector arranged at a first end of the heat exchange surface and a second collector arranged at a second end of the heat exchange surface. heat exchange opposite the first end along the direction of main elongation of the plurality of tubes, the inlet chamber and the outlet chamber of the first circuit and/or of the second circuit being arranged in different manifolds. In other words, the inlet chamber is arranged in the first manifold and the outlet chamber is arranged in the second manifold, or vice versa.

According to one characteristic of the invention, within the at least one circuit configured to form at least two refrigerant fluid circulation passes, the at least one return chamber is formed on one of the first manifold or of the second manifold different from the manifold which includes the inlet chamber and/or the outlet chamber.

According to an alternative of the invention, within the at least one circuit configured to form at least two coolant circulation passes, the at least one return chamber is formed on one of the first manifold or of the second manifold which comprises the inlet chamber and/or the outlet chamber.

According to one characteristic of the invention, at least one separation wall is arranged within at least one of the manifolds so as to form two separate chambers, fluidly connected via tubes of the plurality of tubes.

According to a first example of the invention, the separating wall is arranged between the inlet chamber and the outlet chamber housed in the same collector of one of the circuits. According to another example, the partition wall is arranged between one of the inlet or outlet chambers of one of the circuits and at least one of the return chambers of said circuit, housed in the same collector. According to another example of the invention, the partition wall is arranged between two return chambers of the same circuit, arranged in the same manifold.

According to one characteristic of the invention, the heat exchanger comprises a plurality of heat dissipation members extending along the main direction of elongation of the tubes, each heat dissipation member being placed between at least two tubes of the plurality of tubes along their stacking direction. The heat dissipation members can be, for example and in a non-limiting way, fins, making it possible to increase, by heat conduction between the tubes and these fins, the calorie exchange surface for the air flow passing through the exchanger heat.

According to a characteristic of the invention, the inlet chambers of each of the first circuit and of the second circuit are configured to be fluidically connected in a common manner to an expansion member of the first portion of the refrigerant fluid loop.

It is understood that the branch formed on the first portion of the refrigerant fluid loop which is connected to each of the inlet chambers to supply an equivalent quantity of refrigerant fluid to the first circuit and the second circuit, can be arranged downstream of the expansion member, that is to say between this expansion member and the heat exchanger, so that the portions of refrigerant flowing in each circuit is expanded evenly.

The invention also relates to a refrigerant fluid loop comprising at least one compressor, at least one heat exchanger, at least one heat exchanger according to any one of the preceding characteristics, an outlet of the compressor being fluidly connected to the heat, at least one outlet of the heat exchanger being fluidly connected to the heat exchanger or to an inlet of the compressor, and at least one first expansion member is arranged between the heat exchanger and the heat exchanger and to the at least one second expansion member is arranged between the compressor and the heat exchanger.

According to one characteristic of the refrigerant loop, the latter comprises at least one channel for entering the refrigerant fluid into the heat exchanger and one channel for exiting the refrigerant fluid from the heat exchanger, the inlet chambers of the heat exchanger being fluidically connected to the coolant fluid inlet channel and the heat exchanger outlet chambers being fluidically connected to the coolant fluid outlet channel.

It is also understood that the inlet channel for the coolant in the first inlet chamber and in the second inlet chamber is arranged at the outlet of the expansion device present on the first portion of the coolant loop. The outlet channel, fluidically connected to the first outlet chamber and to the second outlet chamber, is fluidically connected to the compressor or to the heat exchanger depending on the configuration of use of the refrigerant loop.

Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below by way of indication in relation to the drawings in which:

is a schematic view of a refrigerant fluid loop according to a first configuration;

is a schematic view of the refrigerant loop of the according to a second configuration;

is a perspective view of a heat exchanger of the refrigerant loop of Figures 1 and 2, comprising a first circuit and a second circuit and a heat exchange surface comprising a plurality of tubes distributed in a first part and a second part;

is a close-up view of the heat exchange surface illustrating several neighboring tubes and several heat dissipation members respectively arranged between two tubes;

is a schematic view of the heat exchanger of the according to a first example of the invention, in which the directions of circulation of refrigerant fluid have been represented to illustrate the characteristic of the invention according to which at least one circuit of refrigerant fluid comprises two passes;

is a view similar to that of the , illustrating an alternative of the first example of the invention;

is a view similar to that of the , illustrating the heat exchanger according to a second example of the invention;

is a view similar to that of the , illustrating an alternative of the second example of the invention;

is a view similar to that of the , illustrating the heat exchanger according to a third example of the invention.

It should first be noted that if the figures expose the invention in detail for its implementation, these figures can of course be used to better define the invention, if necessary. It should also be noted that these figures only show exemplary embodiments of the invention. Finally, the same references designate the same elements in all the figures.

Figures 1 and 2 illustrate a refrigerant fluid loop 1 according to one aspect of the invention intended to equip a vehicle, electric or hybrid, in order to heat or cool a passenger compartment of the vehicle, by means of a first flow of air 101 directed towards the passenger compartment of the vehicle.

The refrigerant loop 1 comprises at least one heat exchanger 2 specific to the invention, and here comprises, in the example illustrated in FIGS. 1 and 2, a compressor 4, a heat exchanger 6, an evaporator 8 and at least at least one expansion member 10. The heat exchanger 2 is advantageously arranged at the front of the vehicle in order to be crossed by a second flow of air 102 coming from outside the vehicle.

In a first configuration of the refrigerant loop 1, intended to cool the passenger compartment of the vehicle and illustrated here on the , the refrigerant fluid passes through the heat exchanger 2 within which it yields calories to the second air flow 102 passing through the said heat exchanger 2, such that the refrigerant fluid leaves the heat exchanger 2 at the liquid state when it has entered a gaseous state. Subsequently, the refrigerant fluid is directed towards a first expansion member 10a of the refrigerant fluid loop 1, for example an expansion valve, ensuring the expansion of the refrigerant fluid and the lowering of its temperature. Thus, the refrigerant fluid is colder at the outlet of the first expansion member 10a than at the inlet. Following its passage through the first expansion device 10a, the refrigerant fluid passes through the evaporator 8 and exchanges calories with the first air flow 101 passing through the said evaporator 8. More precisely, the evaporator 8 is integrated into a casing of a heating installation of the vehicle which is configured to direct the first flow of air 101 which passes through the evaporator towards the passenger compartment of the vehicle, and the refrigerant fluid circulating in the evaporator is colder than the first flow of air 101 when the latter passes through the evaporator so that the refrigerant fluid is able to capture the calories of the first air flow 101 in order to cool it before it enters the passenger compartment. During the exchange of calories in the evaporator 8, the refrigerant therefore changes to the gaseous state when it captures the calories of the first air flow 101, in particular by lowering its temperature change point. state by the first expansion device 10a.

Subsequently, at the outlet of the evaporator 8, the refrigerant fluid in gaseous form is directed to the compressor 4 which increases the pressure of the refrigerant fluid and therefore increases its temperature. The refrigerant fluid then passes through the heat exchanger 6 without carrying out any heat exchange, said heat exchanger 6 not being, in this configuration of the refrigerant fluid loop 1, crossed by the first air flow 101. At the outlet of the heat exchanger 6, the coolant is directed to a second expansion member 10b which, in this configuration of the coolant loop 1, is inactive, the coolant being directed to the heat exchanger 2 at the outlet of the second expansion device 10b.

In a second configuration of the refrigerant fluid loop 1, intended to heat the passenger compartment of the vehicle and illustrated here on the , the refrigerant passes through the compressor 4 in the gaseous state so that the latter increases the pressure and the temperature of the refrigerant. Subsequently, the refrigerant passes through the heat exchanger 6 within which it exchanges calories with the first air flow 101 which in this configuration passes through the heat exchanger 6 before being directed towards the passenger compartment of the vehicle. More precisely, the coolant transfers its calories to the first air flow 101, which is then colder, so that said first air flow 101 is warmer after having passed through the heat exchanger 6 so as to heat the passenger compartment. of the vehicle.

At the heat exchanger outlet 6, the refrigerant fluid has become liquid but is colder than at the heat exchanger inlet 6 and it is caused to pass through the second expansion member 10b so that the latter further lowers the pressure and the temperature. refrigerant fluid. Subsequently, the refrigerant passes through the heat exchanger 2 in which it exchanges calories with the second air flow 102 passing through it. More precisely, the second air flow 102 is hotter than the refrigerant fluid, and the refrigerant fluid therefore picks up calories from said second air flow 102 during its passage through the heat exchanger 2 and comes out of this last in a gaseous state. Subsequently, the refrigerant, in gaseous state, is redirected to compressor 4.

It is also understood that during the use of the refrigerant loop 1 in the second configuration, which heats the passenger compartment of the vehicle, the cold refrigerant which passes through the heat exchanger 2 captures calories from the second flow of air 102 from outside the vehicle, so that the temperature of the refrigerant increases as it progresses through the heat exchanger 2 from an inlet chamber to an outlet chamber. In addition, it should be considered that when using the refrigerant loop 1 in the second configuration which heats the passenger compartment, that is to say in the winter period, the second air flow 102 is at a low temperature, so that the temperature of the refrigerant fluid may present a negative temperature at the inlet of the heat exchanger and the temperature of the components of this heat exchanger is particularly cold, liable to create frost if droplets of condensation from the second air flow is formed on the surface of the heat exchanger.

The heat exchanger 2 according to the invention, particularly visible in FIGS. 3 to 5, comprises a heat exchange surface 12 extending in a main longitudinal L and vertical V plane 14, and is intended to be crossed by the second air flow 102 from outside the vehicle. The heat exchanger 2 also comprises at least one inlet chamber 16 and an outlet chamber 18 of the refrigerant fluid connected fluidly to the exchange surface 12 so as to respectively allow the entry of the refrigerant fluid into the surface of exchange 12 and the outlet of the coolant from this exchange surface 12, the at least one inlet chamber 16 and the at least one outlet chamber 18 being particularly visible to the .

The heat exchange surface 12 comprises a plurality of tubes 20 stacked along a stacking direction E, here vertical V, and within which the refrigerant fluid circulates. More specifically, the plurality of tubes 20 is configured to channel the refrigerant between the at least one inlet chamber 16 and the at least one outlet chamber 18 along a direction of main elongation A of the tubes 20, here longitudinal L.

The exchange surface 12 of the heat exchanger 2 also comprises a plurality of heat dissipation members 22, visible at the . Each of these heat dissipation members 22 extends parallel to the direction of main elongation A of the tubes 20, over a dimension taken along the direction of main elongation of the tubes 20 substantially identical to a longitudinal dimension of the tubes 20. heat dissipation devices 22 extend between two neighboring tubes 20 of the plurality of tubes 20 and make it possible to increase the contact surface for the second air flow passing through the exchange surface 12, so as to increase the performance of heat exchange. According to an example of the invention, the plurality of heat dissipation members 22 can take the form of spacers or even fins.

According to the invention, the heat exchanger 2 comprises at least a first circuit 24 of refrigerant fluid and a second circuit 26 of refrigerant fluid, visible at the .

The first refrigerant circuit 24 comprises in particular a first part 28a of the plurality of tubes 20, as well as a first inlet chamber 16a and a first outlet chamber 18a which are fluidically connected to tubes of the first part 28a of the plurality of tubes 20. It is understood that the first inlet chamber 16a makes it possible to distribute the refrigerant fluid in each of the tubes of the first part 28a, while the first outlet chamber 18a makes it possible to evacuate the refrigerant fluid once it circulated through the tubes of the first part 28a.

More specifically, the first inlet chamber 16a is fluidically connected to a first portion 30a of the refrigerant fluid loop 1, visible in Figures 1 and 2, arranged between the heat exchanger 6, here in the form of a condenser, and the heat exchanger, and comprising the second expansion member 10b, mentioned above. Furthermore, the first outlet chamber 18a is fluidically connected to a second portion 30b of the refrigerant fluid loop 1, connected to the evaporator 8 or to the compressor 4 depending on the configuration of the thermal regulation loop.

The second circuit 26 of refrigerant fluid comprises a second part 28b of the plurality of tubes 20 of refrigerant fluid, as well as a second inlet chamber 16b and a second outlet chamber 18b which are fluidically connected to tubes 20 of the second part 28b of the plurality of tubes 20. In accordance with what has been described previously, the second inlet chamber 16b makes it possible to distribute the refrigerant fluid in each of the tubes of the second part 28b, while the second outlet chamber 18b makes it possible to evacuate the refrigerant fluid once it has circulated through the tubes of the second part 28b.

The second inlet chamber 16b is fluidically connected to the first portion 30a of the refrigerant fluid loop 1 previously described and visible in Figures 1 and 2, while the second outlet chamber 18b is fluidically connected to the second portion 30b of the refrigerant loop 1.

The first part 28a of the plurality of tubes 20 and the second part 28b of the plurality of tubes 20 are fluidically distinct from each other. The first inlet chamber 16a and the second inlet chamber 16b being configured to be fluidically connected to the same first portion 30a of the refrigerant loop, it is understood that this first portion comprises a branch with two branches to which are connected the first inlet chamber 16a and the second inlet chamber 16b. The refrigerant circulating in the first portion 30a of the refrigerant loop is split on passing this branch into two flow portions circulating, one in the first circuit via the first inlet chamber and the other in the second circuit. via the second entrance chamber.

The first inlet chamber 16a and the second inlet chamber 16b are configured to be fluidically connected in a common manner to the second expansion device of the refrigerant loop. More precisely, an inlet channel 32 of the coolant fluid in the heat exchanger 2, visible in FIGS. 1 and 2, and an outlet channel 34 of the coolant fluid of the heat exchanger 2 are defined. inlet 16a, 16b are then fluidically connected to the inlet channel 32 of the refrigerant fluid while the outlet chambers 18a, 18b are fluidically connected to the outlet channel 34 of the refrigerant fluid. In other words, the inlet channel 32 of the refrigerant fluid extends between the second expansion member 10b and the inlet chambers 16a, 16b, while the outlet channel 34 extends between the outlet chambers 18a, 18b and the compressor 4 or the evaporator 8 depending on the configuration of the refrigerant loop 1.

At least one of the tubes 20 of the first circuit 24 is arranged between two tubes 20 of the second circuit 26 along the direction of stacks E of the tubes 20 and/or at least one of the tubes 20 of the second circuit 26 is arranged between two tubes 20 of the first circuit 24 along the stacking direction E of the tubes 20. Such an alternate arrangement of the tubes 20 of the first circuit 24 and the tubes 20 of the second circuit 26 is advantageous for better homogenizing the temperature of the components of the exchanger heat when the refrigerant circulates within the heat exchange surface.

The exchange surface 12 extends longitudinally between a first end 36 of the exchange surface and a second end 38 of the exchange surface, these ends being opposite to each other in the direction of elongation. main A of the plurality of tubes 20. Collectors are arranged at each of these ends, the inlet and outlet chambers mentioned above being formed in these collectors.

The heat exchanger 2 comprises at least a first collector 40a arranged at the first end 36 of the exchange surface 12 and at least a second collector 40b arranged at the second end 38 of the exchange surface 12. precisely, and according to the example of the invention, the heat exchanger 2 comprises the first collector 40a and the second collector 40b, arranged on either side of the plurality of tubes to form the first circuit 24, and the second circuit 26 comprises a third collector 40c at the first end 36 of the exchange surface 12 and a fourth collector 40d at the second end 38 of the exchange surface 12, arranged on either side of the plurality of tubes to form the second circuit 26.

According to the example of the invention of the , the first collector 40a and the second collector 40b of the first circuit 24 face each other in the direction of main elongation A of the tubes 20. Similarly, the third collector 40c and the fourth collector 40d of the second circuit 26 are facing each other in the direction of main elongation A of the tubes 20. Furthermore, and still according to an example of the invention, the first collector 40a and the third collector 40c positioned at the first end 36 of the exchange surface 12 are aligned along a line I secant to the main plane 14 of the exchange surface 12, said line I being for example perpendicular to said main plane 14. It should be considered that this characteristic applies mutatis mutandis to the second collector 40b and to the fourth collector 40d positioned at the second end 38 of the exchange surface 12. In this way, the main plane 14 of the exchange surface forms a plane of symmetry on both sides on the other of which the collectors are arranged, with the first collector 40a and the second collector 40b arranged on one side of the exchange surface, on either side of the tubes, and with the third collector 40c and the fourth collector 40d arranged on the other side of the exchange surface by forming a mirror image of the first collector 40a and the second collector 40b.

The circuits, the chambers and the collectors are arranged within the heat exchanger according to the invention in such a way that the refrigerant fluid can circulate in two passes within at least one of the circuits 24, 26. in other words, at least one of the first circuit 24 and/or of the second circuit 26 comprises at least one refrigerant fluid return chamber, fluidly arranged between the inlet chamber 16 and the outlet chamber 18 of the circuit 24, 26 concerned, this return chamber making it possible to redirect the refrigerant fluid in an opposite direction of circulation so as to cause the refrigerant fluid to circulate in two neighboring tubes in opposite directions.

A first exemplary embodiment will now be described, with reference to the . The first inlet chamber 16a and the first outlet chamber 18a of the first circuit 24 are arranged in the same collector, and more particularly the first collector 40a. Furthermore, the second inlet chamber 16b and the second outlet chamber 18b of the second circuit 26 are arranged respectively in the third collector 40c and the fourth collector 40d. In this way, the first circuit 24 is configured so that the coolant is intended to enter and leave the exchange surface 12 via the same first manifold 40a, while the second circuit 26 is configured so that the coolant enters the exchange surface 12 by the third collector 40c and leaves the exchange surface 12 by the fourth collector 40d.

A separation wall 42 notably makes it possible to fluidically separate the first inlet chamber 16a and the first outlet chamber 18a within the first collector of the first circuit. It should be considered that in the rest of the description, a separation wall 42 is arranged in a manifold 40 when two chambers are formed within this manifold, so as to fluidically isolate these chambers from each other.

It is then understood from the above that the first inlet chamber 16a and the first outlet chamber 18a share an internal volume 46 of the first manifold 40a, being separated by the separation wall 42. As illustrated, the volume of each of these two chambers can be the same, and represent substantially half of the internal volume 46 of the first manifold 40a.

The first inlet chamber 16a of the first circuit 24 is fluidically connected to a first portion 48a of the first part 28a of the plurality of tubes 20 while the first outlet chamber 18a of the first circuit 24 is fluidically connected to a second portion 48b of the first part 28a of the plurality of tubes 20. In other words, the first inlet chamber 16a and the second inlet chamber 16b of the first circuit 24 are fluidically connected to separate tubes 20 of the first part 28a of the plurality of tubes 20. In the example mentioned where the volume of each of the two chambers is substantially equal to half the internal volume 46 of the first manifold 40a, said first portion 48a and second portion 48b each comprise half of the tubes 20 forming the first part 28a of the plurality of tubes 20.

As mentioned, at least one coolant fluid return chamber 44 is fluidly disposed between the inlet chamber 16 and the outlet chamber 18. In the first example of the invention illustrated in the , the first circuit 24 comprises a first return chamber 44a housed within the second collector 40b and the second circuit has no return chamber.

The return chamber 44, 44a of the first circuit 24, housed within the second manifold 40b, also extends throughout an internal volume 46 of the second manifold 40b, such that the return chamber 44 of the first circuit 24 is fluidly connected to all of the tubes 20 of the first part 28a of the plurality of tubes 20. In other words, here, the return chamber 44 of the first circuit 24 is connected to all of the tubes 20 connected to the first inlet chamber 16a and to all the tubes connected to the first outlet chamber 18a.

Concerning the second circuit 26, the second inlet chamber 16b housed in the third manifold 40c extends over an entire internal volume 46 of said third manifold 40c and is thus fluidly connected to all of the tubes 20 of the second part 28b of the plurality of tubes 20. Similarly, the second outlet chamber 18b of the second circuit 26 housed in the fourth manifold 40d extends throughout an internal volume 46 of said fourth manifold 40d and is thus fluidly connected to all of the tubes 20 of the second part 28b of the plurality of tubes 20.

In accordance with the invention, in the first embodiment of the invention, at least one circuit, namely here the first circuit 24, of refrigerant fluid formed within the heat exchanger 2 is configured to present at least two passes 50 in the exchange surface 12 between its first inlet chamber 16a and its first outlet chamber 18a. In other words, within the first refrigerant circulation circuit 24, which is represented arbitrarily on this by simple arrows, the refrigerant fluid is configured to circulate in opposite directions of circulation forming a first pass 50a in which the refrigerant fluid circulates in a first circulation direction S1 and a second pass 50b in which the refrigerant fluid circulates in a second direction S2 of circulation, opposite to the first direction S1 along the direction of elongation A of the tubes 20.

More precisely and according to this first example of the invention, the first pass 50a of the first circuit 24 extends from the first inlet chamber 16a to the first return chamber 44a passing through the first portion 48a of the first part 28a of the plurality of tubes 20. In this first pass 50a, the refrigerant fluid therefore circulates from the first inlet chamber 16a to the first return chamber 44a in the first direction S1 of circulation, parallel to the direction d elongation A of the tubes 20. Once arrived in the first return chamber 44a after having passed through the first pass 50a, the coolant is reinjected into the exchange surface 12, and in particular into the second portion 48b of the first part 28a of the plurality of tubes 20, as far as the first outlet chamber 18a, so as to form the second pass 50b, by circulating in the second direction S2 of circulation.

As mentioned, in this example of the invention, the second circuit 26 is configured so as to form a single pass 50 for the circulation of refrigerant fluid in the exchange surface 12, the refrigerant fluid circulating in a single direction of circulation, here the first direction S1 of circulation, from the second inlet chamber 16b housed in the third collector 40c to the second outlet chamber 18b housed in the fourth collector 40d, as shown arbitrarily on the by double arrows.

This arrangement of the heat exchanger allows the implementation of a cross circulation of the coolant in at least one zone of the exchange surface 12. The coolant is made to circulate in the plurality of tubes 20 of the surface exchanger 12 of the heat exchanger 2 according to two opposite directions S1, S2 of circulation whether within the first or the second circuit, since at least one of the circuits has at least two passes of circulation in opposite directions and that as a result, in at least one zone of the exchange surface, at least two tubes adjacent to the exchange surface are traversed by a refrigerant fluid flowing in opposite directions, it being understood that the plurality of tubes forming the heat exchange surface extending in the same plane are distributed between the first circuit and the second circuit. In the case where the tubes forming the heat exchange surface are arranged alternately, with at least one of the tubes 20 of the first circuit 24 which is arranged between two tubes 20 of the second circuit 26 along the direction of stacks E of the tubes 20 and/or at least one of the tubes 20 of the second circuit 26 which is arranged between two tubes 20 of the first circuit 24 along the stacking direction E of the tubes 20, the zone of the heat exchange surface heat on which the flow of refrigerant is in opposite directions is enlarged. And this zone is all the larger as the tubes of the first circuit and the tubes of the second circuit are arranged in a regular and repeated alternation over the entire heat exchange surface, which makes it possible to better homogenize the temperature of the components of the heat exchanger when the refrigerant circulates within the heat exchange surface.

More specifically, in the first embodiment of the heat exchanger, in the first circuit 24, the refrigerant fluid circulates in the first pass 50a along the first direction S1 of circulation in the first portion of tubes 48a, that is- that is to say from the first end 36 of the exchange surface towards the second end 38 of the exchange surface, then in the second pass 50b following the second direction S2 of circulation in the second portion of tubes 48b, it is that is to say from the second end 38 of the exchange surface 12 towards the first end 36 of the exchange surface 12. And in the second circuit 26, the refrigerant fluid circulates only in the first direction S1 of circulation, from the first end 36 of the exchange surface towards the second end 38 of the exchange surface. In the zone where the tubes of the second circuit 26 are arranged alternately with the tubes of the first portion of tubes 48 of the first circuit, the refrigerant fluid circulates in the same direction of circulation whether in the first circuit or in the second circuit. . But in the zone where the tubes of the second circuit 26 are arranged alternately with the tubes of the second portion of tubes 48 of the first circuit, the refrigerant fluid circulates in opposite directions of circulation depending on whether it circulates in the first circuit or in the second circuit.

Such cross-circulation of the refrigerant fluid within the heat exchanger 2 advantageously makes it possible to obtain a better temperature distribution within the exchange surface 12. In other words, the temperature gradient of the refrigerant fluid circulating within the first circuit 24, and in particular at the level of the second pass 50b, is opposed to the temperature gradient of the refrigerant fluid circulating within the second circuit 26, thus limiting the concentration of low or negative temperature in a localized zone of the exchange surface 12, which thus makes it possible to limit the formation of frost on said heat exchange surface 12 .

Alternatively, as illustrated in the exemplary embodiment of the , the second circuit 26 may comprise a configuration identical to the first circuit 24 of the first example of the invention, namely a configuration with two passes, each of the first circuit 24 and of the second circuit 26 then comprising a return chamber 44 as described previously. In such a configuration, the first circuit 24 and the second circuit 26 therefore comprise an identical number of passes 50 . As shown on the , each of the inlet chambers 16 and the outlet chambers 18 of the first circuit 24 and of the second circuit 26 are housed respectively within the first collector 40a and the third collector 40c, that is to say at the same first end 36 of the exchange surface 12. Similarly, each of the return chambers 44 of the first circuit 24 and of the second circuit 26 is housed respectively in the second collector 40b and in the fourth collector 40d, that is to say at the same second end 38 of the heat exchange surface 12.

Furthermore, a first vertical end 52a of the heat exchanger 2 and a second vertical end 52b of the heat exchanger 2 are defined, opposite to each other in the stacking direction E of the tubes 20. The inlet chamber 16a of the first circuit 24 and the inlet chamber 16b of the second circuit 26 are then respectively housed in the first collector 40a and the third collector 40c at opposite vertical ends 52a, 52b of the heat exchanger 2 More precisely, the first inlet chamber 16a of the first circuit 24 is housed in the first collector 40a at the level of the first vertical end 52a of the heat exchanger 2 while the second inlet chamber 16b of the second circuit 26 is housed in the third manifold 40c at the level of the second vertical end 52b of the heat exchanger 2. This ensures the cross circulation of the refrigerant fluid circulating in the first circuit 24 and in the second circuit 26 on the whole of the heat exchange surface, and no longer as illustrated in the on only a zone corresponding to the second portion of tubes 48b of the first circuit.

Other examples of the invention will now be described in the remainder of the description by means of FIGS. 7 to 9. It should then be considered that only the distinct characteristics with the first example of the invention will be the subject of a detailed description, and that reference should be made to the description given with reference to FIGS. 1 to 6 for the common characteristics.

In the second embodiment of the , only the first circuit will be described, the second circuit being identical to the first example of the invention, visible in , with a single pass.

As seen on the , the first circuit 24 of the heat exchanger 2 comprises the first return chamber 44a and a second return chamber 44b. The first inlet chamber 16a and the second return chamber 44b are housed in the second collector 40b while the first return chamber 44a and the first outlet chamber 18a are housed in the first collector 40a. More particularly, the first inlet chamber 16a is arranged in the second manifold 40b at the level of the second vertical end 52b while the first outlet chamber 18a is arranged in the first manifold 40a at the level of the first vertical end 52a of the heat exchanger 2.

Considering that two chambers are facing each other when they are arranged on either side of the heat exchange surface for a given tube, the first inlet chamber 16a is facing the first return chamber 44a while the first outlet chamber 18a faces the second return chamber 44b along the main elongation direction A of the tubes, part of the first return chamber 44a being opposite the second referral chamber.

For this purpose, a first vertical dimension DV1 of the first inlet chamber 16a and a second vertical dimension DV2 of the second outlet chamber 18b are defined, taken along the stacking direction E of the tubes 20, the first vertical dimension DV1 and the second vertical dimension DV2 being equal to each other. Furthermore, a first vertical height DH1 of the first return chamber 44a and a second vertical height DH2 of the second return chamber 44b are defined, taken along the stacking direction E of the tubes 20, said first vertical height DH1 and second vertical height DH2 being substantially equal to each other.

According to this second embodiment of the invention, the first vertical height DH1 and the second vertical height DH2 of the return chambers 44 are strictly greater than the first vertical dimension DV1 and the second vertical dimension DV2. More specifically, the vertical heights DH1, Dh2 of the return chambers 44 are substantially equal to twice the vertical dimensions DV1, DV2 of the inlet 16 and outlet 18 chambers. It is therefore understood that in this second embodiment of the invention, the first portion 48a of the first part 28a of the plurality of tubes 20 fluidly connected to the first inlet chamber 16a as well as the second portion 48b of the first part 28a of the plurality of tubes 20, fluidly connected to the first outlet chamber 18a, have fewer tubes 20 than in the first example of the invention.

In this way, in this second example of the invention, the first circuit 24 comprises a third portion 48c of the first part 28a of the plurality of tubes 20, distinct from the first portion 48a and from the second portion 48b and arranged fluidly between the latter, being arranged between the two facing return chambers. It is therefore understood that the first portion 48a, the second portion 48b and the third portion 48c form the first part 28a of the plurality of tubes 20. Each of the first portion 48a, the second portion 48b and the third portion 48c of the first part 28a of the plurality of tubes 20 represents substantially an equal part, here one third, of a quantity of tubes 20 of the first part 28a of the plurality of tubes 20.

In doing so, in this second example of the invention, the first return chamber 44a is fluidly connected to the first portion 48a and the third portion 48c of the first part 28a of the plurality of tubes 20 and the second return chamber 44b is fluidly connected to the second portion 48b and the third portion 48c of the first part 28a of the plurality of tubes 20. In other words, the first return chamber 44a is fluidically connected to all the tubes 20 connected to the first inlet chamber 16a and tubes 20 connected to the second return chamber 44b, corresponding here to the third portion 48c. Similarly, the second return chamber 44b is fluidly connected to all of the tubes 20 connected to the first outlet chamber 18a and to the tubes 20 connected to the first return chamber 44a, corresponding here to the third portion 48c.

Thus, in the first circuit 24 of this second example of the invention, the refrigerant circulates from the first inlet chamber 16a to the first return chamber 44a in the second direction S2 of circulation, in the first portion 48a of the first part 28a of the plurality of tubes 20 forming the first pass 50a, then from the first return chamber 44a to the second return chamber 44b along the first direction S1 of circulation, in the third portion 48c of the first part 28a of the plurality of tubes 20 forming the second pass 50b, and finally from the second return chamber 44b to the first outlet chamber 18a, in the second portion 48b of the first part 28a of the plurality of tubes 20, along the second direction S2 of circulation, forming a third pass 50c. It is understood that here the first circuit 24 comprises three passes 50 ensuring cross circulation of the refrigerant fluid within the first circuit 24 and between the refrigerant fluid circulating in the first circuit 24 and the refrigerant fluid circulating in the second circuit 26 following the first direction S1 of traffic, in a single pass 50.

In accordance with what has been described for the first example, an alternative to this second example can be provided, with reference to the , with the second circuit 26 which may comprise a configuration identical to the first circuit 24 as just mentioned in this second example of the invention.

More particularly the first circuit 24 and the second circuit 26 comprise an identical number of passes 50, namely three passes 50, each of the first circuit 24 and of the second circuit 26 comprising the first return chamber 44a and the second return chamber 44b fluidically arranged between the inlet chamber 16 and the outlet chamber 18 of each of the circuits 24, 26, as was described for the first circuit 24 of the second example of the invention. The second inlet chamber 16b of the second circuit 26 is here housed in the fourth collector 40d at the level of the first vertical end 52a, that is to say opposite the first inlet chamber 16a of the first circuit 24 along the vertical direction V of the heat exchanger 2. Similarly, the second outlet chamber 18b of the second circuit 26 is housed in the third manifold 40c at the level of the second vertical end 52b of the heat exchanger 2 of so as to be vertically opposed to the first outlet chamber 18a of the first circuit 24 housed in the first collector 40a at the level of the first vertical end 52a of the heat exchanger 2.

Here again, in this alternative, the cross circulation of the refrigerant fluid circulating in the first circuit 24 and in the second circuit 26 is thus ensured over the whole of the heat exchange surface, and no longer as illustrated in on only a zone corresponding to the third portion of tubes 48c of the first circuit.

A third example of the invention will now be described in connection with the . Only the distinct characteristics of the preceding examples of the invention will be the subject of a detailed description, and reference should be made to the examples of the invention described with reference to the preceding figures for the common characteristics.

In this third example of the invention, the second circuit 26 comprises two passes 50 as described in , the second inlet chamber 16b and the second outlet chamber 18b being housed in the third manifold 40c of the heat exchanger 2, respectively at its first vertical end 52a and its second vertical end 52b.

The first circuit 24 is configured to form four coolant circulation passes, so that the first circuit and the second circuit each comprise a different number of passes from one another.

More particularly, the first circuit 24 according to this third example of the invention comprises a third return chamber 44c fluidly arranged between the second return chamber 44b and the first outlet chamber 18a. Thus, the first collector 40a houses the first return chamber 44a and the third return chamber 44c, respectively at the first vertical end 52a and the second vertical end 52b of the heat exchanger 2. Similarly, the second collector 40b houses the first inlet chamber 16a, the second return chamber 44b and the first outlet chamber 18a, the first inlet chamber 16a being at the level of the first vertical end 52a of the heat exchanger 2, the first outlet 18a being at the second vertical end 52b of heat exchanger 2 and second return chamber 44b extending between first inlet chamber 16a and first outlet chamber 18a.

It is further understood that the first part 28a of the plurality of tubes 20 here comprises a fourth portion 48d fluidly connected to the third return chamber 44c. Thus, the first portion 48a of the first part 28a of the plurality of tubes 20 extends between the first inlet chamber 16a and the first return chamber 44a, the third portion 48c of the first part 28a of the plurality of tubes 20 extends between the first return chamber 44a and the second return chamber 44b, the fourth portion 48d of the first part 28a of the plurality of tubes 20 extends between the second return chamber 44b and the third return chamber 44c and the second portion 48b of the first part 28a of the plurality of tubes 20 extends between the third return chamber 44c and the first outlet chamber 18a.

Thus, in this third example of the invention, the coolant is intended to circulate from the first inlet chamber 16a to the first return chamber 44a in the second direction S2 of circulation, forming the first pass 50a, then from the first return chamber 44a to the second return chamber 44b in the first direction S1 of circulation, forming the second pass 50b, and from the second return chamber 44b to the third return chamber 44c in the second direction S2 of circulation, forming the third pass 50c and finally from the third return chamber 44c to the first exit chamber 18a along the first direction S1 of circulation, forming a fourth pass 50d.

It is thus understood that the first pass 50a and the fourth pass 50d of the first circuit 24 have opposite directions S1, S2 of circulation, respectively to the first pass 50a and the second pass 50b of the second circuit 26 ensuring cross circulation of the refrigerant within the heat exchange surface 12. The second pass 50b and the third pass 50c make it possible to increase the distribution of the temperature gradient within the exchange surface 12, said second pass 50b and third pass 50c ensuring the circulation of the refrigerant fluid in opposite directions S of circulation .

The invention as it has just been described cannot however be limited to the means and configurations exclusively described and illustrated, and also applies to all equivalent means or configurations and to any combination of such means or configurations.

Claims (10)

Heat exchanger (2) for a refrigerant loop (1), comprising a heat exchange surface (12), the heat exchange surface (12) comprising a plurality of tubes (20), the exchanger heat (2) being characterized in that it comprises at least a first circuit (24) of refrigerant fluid consisting of a first part (28a) of the plurality of tubes (20), a first inlet chamber (16a) fluidly connected to tubes (20) of the first part (28a) of the plurality of tubes (20) and a first outlet chamber (18a) fluidly connected to tubes (20) of the first part ( 28a) of the plurality of tubes (20), the heat exchanger (2) comprising at least a second refrigerant fluid circuit (26) consisting of a second part (28b) of the plurality of tubes (20), d a second inlet chamber (16b) fluidly connected to tubes (20) of the second part (28b) of the plurality of tubes (20) and a second outlet chamber (18b) fluidly connected to tubes ( 20) of the second part (28b) of the plurality of tubes (20), the first part (28a) of the plurality of tubes (20) and the second part (28b) of the plurality of tubes (20) being fluidly distinct from each other and at least one of the first circuit (24) and/or of the second circuit (26) being configured to form in the exchange surface (12) at least two fluid circulation passes (50) refrigerant between the inlet chamber (16) and the outlet chamber (18) of said circuit. Heat exchanger (2) according to the preceding claim, in which, within the at least one circuit (24, 26) configured to form at least two coolant circulation passes (50), a return chamber (44 ) of the refrigerant is fluidly disposed between the inlet chamber (16) and the outlet chamber (18) of said corresponding circuit. Heat exchanger (2) according to the preceding claim, in which, within the at least one circuit (24, 26) configured to form at least two coolant circulation passes (50), the at least one return (44) of the refrigerant fluid is fluidly connected to the set of tubes (20) connected to the inlet chamber (16) and to the set of tubes (20) connected to the outlet chamber (18). Heat exchanger (2) according to Claim 2, in which, within the at least one circuit (24, 26) configured to form at least two coolant circulation passes (50), a first return chamber ( 44a) of the refrigerant fluid is fluidly connected to the set of tubes (20) connected to the inlet chamber (16) or to the outlet chamber (18) and to a plurality of tubes (20) connected to a second chamber reference (44b). Heat exchanger (2) according to any one of the preceding claims, in which at least one of the first circuit (24) and/or of the second circuit (26) comprises a first collector (40a) disposed at a first end (36) of the heat exchange surface (12) and a second collector (40b) disposed at a second end (38) of the heat exchange surface (12) opposite the first end (36) along the direction of main elongation (A) of the plurality of tubes (20), the inlet chamber (16) and the outlet chamber (18) of the first circuit (24) and/or of the second circuit (26) being arranged in the same first manifold (40a) or second manifold (40b). Heat exchanger (2) according to any one of Claims 1 to 4, in which at least one of the first circuit (24) and/or of the second circuit (26) comprises a first collector (40a) arranged at a first end ( 36) of the heat exchange surface (12) and a second collector (40b) disposed at a second end (38) of the heat exchange surface (12) opposite the first end (36) along the direction of main elongation (A) of the plurality of tubes (20), the inlet chamber (16) and the outlet chamber (18) of the first circuit (24) and/or of the second circuit (26) being arranged in different collectors (40a, 40b). Heat exchanger (2) according to any one of Claims 5 to 6, in which at least one separating wall (42) is arranged within at least one of the collectors (40a, 40b) so as to form two separate chambers (16, 18, 44) fluidly connected through the plurality of tubes. A heat exchanger (2) according to any preceding claim, wherein the inlet chambers (16) of each of the first circuit (24) and the second circuit (26) are configured to be fluidly connected in common to an expansion device (10, 10a, 10b) for the first portion of the refrigerant fluid loop (1). Refrigerant fluid loop (1) comprising at least one compressor (4), at least one heat exchanger (8), at least one heat exchanger (2) according to any one of the preceding claims, an outlet of the compressor (4) being fluidly connected to the heat exchanger (2), at least one outlet of the heat exchanger (2) being fluidically connected to the heat exchanger (8) or to an inlet of the compressor (4), and at least a first expansion member (10a) is arranged between the heat exchanger (2) and the heat exchanger (8) and at least one second expansion member (10b) is arranged between the compressor (4) and the heat exchanger heat (2). Cooling fluid loop (1) according to the preceding claim comprising at least one coolant fluid inlet channel (32) in the heat exchanger (2) and a coolant fluid outlet channel (34) from the heat exchanger. (2), the inlet chambers (16) of the heat exchanger (2) being fluidly connected to the inlet channel (32) of the refrigerant fluid and the outlet chambers (18) of the heat exchanger (2) being fluidly connected to the outlet channel (34) of the coolant fluid.