Thermal management system and method for a motor vehicle comprising a hydrogen powertrain

Abstract

TITLE: Thermal Management System and Method for a Motor Vehicle Comprising a Hydrogen Powertrain. Thermal management system (2) for a motor vehicle (1) comprising a hydrogen powertrain (3), including a primary boost circuit (4) with a primary cooling module (42), a secondary circuit (5) for circulating a heat transfer fluid (RF) with a secondary cooling module (51), the system further comprising a heat exchanger configured to implement heat exchange between the boost airflow (FAS) circulating in the primary circuit (4) and the heat transfer fluid (RF) circulating in the secondary circuit (5). Abstract Figure: Figure 1

Description

Title of the invention: System and method for thermal management of a motor vehicle comprising a hydrogen powertrain

[0001] The invention relates to a thermal management system for a motor vehicle, in particular one equipped with a hydrogen powertrain. The invention further relates to a motor vehicle equipped with said system. The invention also relates to a method for thermal management of a motor vehicle.

[0002] In a context where manufacturers are turning towards low-emission vehicles, internal combustion engines are well-suited for implementing hydrogen powertrains, i.e., using dihydrogen as fuel. However, hydrogen powertrains are subject to different design constraints than combustion engines using gasoline or diesel.

[0003] In particular, in order to achieve a high level of performance, for example targeted in sports applications, it is necessary to take into account the fact that hydrogen has a lower energy density than gasoline. It is known to compensate for this deficit by operating at higher temperatures but also by working on engine efficiency.

[0004] Implementing higher combustion temperatures requires developing more efficient thermal management systems that meet the requirements for engine component durability, i.e., the longevity of its components, as well as performance requirements, i.e., the ability to withstand high maximum power outputs repeatedly. Known hydrogen-powered vehicles are equipped with cooling systems comprising a circuit in which a heat transfer fluid circulates. This fluid heats up upon contact with the vehicle's components and cools down as it passes through a heat exchanger. The system also includes a circuit configured to allow the circulation of a cooling fluid, also referred to as a water circuit, which limits the temperature rise of the powertrain cylinder head.One drawback of known systems lies in the considerable size and bulk of the heat exchanger used, which limits the vehicle's performance and impacts its aerodynamics.

[0005] The invention falls within this context and aims to provide a system and method for thermal management of a motor vehicle that overcomes the above drawbacks. In particular, the invention proposes a thermal management system for a motor vehicle comprising

[0006] The invention relates to a thermal management system for a motor vehicle equipped with a hydrogen powertrain, the thermal management system comprising: - at least one primary boost circuit capable of allowing the circulation of a boost airflow, said circuit comprising a turbocharger, a primary cooling module comprising a primary set of controlled flaps and a primary heat exchanger configured to implement heat exchange between the boost airflow and an airflow external to the vehicle; - at least one secondary circulation circuit for a heat transfer fluid comprising a hydrogen powertrain and a secondary cooling module comprising a secondary set of controlled flaps and a heat exchanger configured to implement heat exchange between the heat transfer fluid and the airflow outside the vehicle.

[0007] The system further comprises a means for controlling the primary set of flaps and the secondary set of flaps and at least one secondary heat exchanger configured to implement heat exchange between the supercharge airflow circulating in at least one primary circuit and the heat transfer fluid circulating in at least one secondary circuit.

[0008] In particular, at least one secondary heat exchanger: - is positioned downstream of the turbocharger and upstream of the primary heat exchanger in a direction of flow of the supercharged air; and - is positioned downstream of the powertrain and upstream of at least one heat exchanger in a direction of flow of the heat transfer fluid.

[0009] According to one embodiment, at least one primary cooling module is at least partly arranged upstream of at least one secondary cooling module in a direction of circulation of the outside air flow, the primary set of flaps being arranged so as to regulate the circulation of at least a part of the outside air flow intended to circulate successively through the primary heat exchanger and then the heat exchanger.

[0010] According to a particular embodiment, the thermal management system comprises: - a plurality of primary supercharging circuits, each being capable of allowing the circulation of a supercharging airflow specific to it and each of said circuits comprising a turbocharger, a primary cooling module comprising a primary set of flaps and a primary heat exchanger configured to implement heat exchange between the supercharging airflow specific to said circuit and an airflow external to the vehicle; - a plurality of secondary circuits for circulating a heat transfer fluid, each comprising at least a part of the powertrain and a secondary cooling module comprising a secondary set of flaps and a heat exchanger configured to implement heat exchange between the heat transfer fluid and the airflow outside the vehicle.

[0011] The system then further comprises a plurality of secondary heat exchangers, each configured to implement a heat exchange between the supercharge airflow circulating in one of the primary circuits and the heat transfer fluid circulating in one of the secondary circuits.

[0012] In other words, in such an embodiment, at least one primary boost circuit, also referred to as the first primary boost circuit, includes a first turbocharger, a first primary cooling module comprising a first primary set of controlled flaps and a first primary heat exchanger, and at least one secondary heat transfer fluid circulation circuit, also referred to as the first secondary circuit, includes the powertrain, a first secondary cooling module, comprising a first secondary set of controlled flaps and a first heat exchanger.

[0013] Also in such an embodiment, the thermal management system comprises: - a second primary boost circuit comprising a second turbocharger, a second primary cooling module comprising a second primary set of controlled flaps and a second primary heat exchanger configured to implement heat exchange between the boost airflow circulating in said second primary circuit and an airflow external to the vehicle; - a second secondary heat transfer fluid circulation circuit, comprising the powertrain, a second secondary cooling module, comprising a second secondary set of controlled flaps and a second heat exchanger; and - at least one secondary heat exchanger, referred to as the first secondary heat exchanger, configured to implement heat exchange between the charge airflow circulating in the first primary circuit and the heat transfer fluid circulating in the first secondary circuit, and a second secondary heat exchanger, configured to implement heat exchange between the charge airflow circulating in the second primary circuit and the heat transfer fluid circulating in the second secondary circuit.

[0014] For example, the management system includes at least one pump arranged so as to be common to the plurality of secondary circuits for circulating a heat transfer fluid.

[0015] The invention also relates to a motor vehicle comprising the thermal management system according to the invention.

[0016] The invention further relates to a method for thermal management of a motor vehicle according to the invention, the vehicle being equipped with at least one primary temperature sensor, capable of measuring the temperature of the supercharged airflow at at least one point in at least one primary circuit, and a secondary temperature sensor configured to measure the temperature of the heat transfer fluid at at least one point in at least one secondary circuit, the method comprising: - a step of measuring the temperature of the supercharged airflow and the heat transfer fluid via the primary temperature sensor and the secondary temperature sensor respectively; - a step of determining a thermal management method to be applied based on the measured temperatures; - a step of applying the thermal management mode determined by adjusting a degree of opening of at least the primary set of flaps and / or the secondary set of flaps by means of the control means, the primary set of flaps being open when the temperature of the supercharge airflow is greater than or equal to a first primary temperature threshold and / or the secondary set of flaps being open when the temperature of the heat transfer fluid is greater than or equal to a first secondary temperature threshold.

[0017] In particular, at least one primary cooling module includes a primary motor-fan assembly and at least one secondary cooling module includes a secondary motor-fan assembly, the thermal management mode application step including the adjustment of an operating mode of the primary motor-fan assembly when the temperature of the charge airflow is greater than or equal to a second primary temperature threshold, greater than the first primary temperature threshold, and / or the adjustment of an operating mode of the secondary motor-fan assembly when the temperature of the heat transfer fluid is greater than or equal to a second secondary temperature threshold, greater than the first secondary temperature threshold.

[0018] In particular, the step of applying the thermal management mode to be applied includes limiting the torque of the powertrain when the temperature of the supercharged airflow is greater than or equal to a third primary temperature threshold.

[0019] The invention further extends to a computer program product comprising program code instructions recorded on a computer-readable medium to implement the steps of the thermal management process according to the invention when said program is running on a computer.

[0020] Other details, features and advantages will become clearer upon reading the detailed description given below, by way of example and not limitation, in relation to the various embodiments illustrated in the following figures:

[0021] Fig. 1 is a simplified schematic representation of an example of an implementation of a thermal management system implemented in a "small displacement" type vehicle.

[0022] Fig. 2 is a schematic representation of an example embodiment of a vehicle including the thermal management system illustrated in Fig. 1.

[0023] Fig. 3 is a schematic representation of a first example of an arrangement of separate exchangers included in the thermal management system illustrated in Fig. 1 or 2.

[0024] Fig. 4 is a schematic representation of an example embodiment of a vehicle comprising a separate arrangement of heat exchangers of the thermal management system illustrated in Fig. 1.

[0025] Fig. 5 is a schematic representation of the arrangement of exchangers illustrated in Fig. 4.

[0026] Fig. 6 is a simplified schematic representation of an example of the thermal management system implemented in a vehicle of the "large displacement" type.

[0027] Fig. 7 is a schematic representation of an example embodiment of a vehicle including the thermal management system illustrated in Fig. 6.

[0028] Fig. 8 is a schematic representation of another example of arrangement of separate exchangers included in the thermal management system illustrated in Fig. 6 or 7.

[0029] Fig. 9 is a flowchart detailing an example of the execution of the thermal management process according to the invention.

[0030] Fig. 10 is a flowchart detailing an example of the execution of the thermal management process according to the invention.

[0031] Figures 1 to 8 schematically illustrate a motor vehicle 1 equipped with an embodiment of a thermal management system 2 according to the invention. The vehicle 1 can be of any type, that is to say, it can be a passenger car, a sports car, a commercial vehicle, a truck or a bus.

[0032] In particular, the vehicle 1 comprises a hydrogen powertrain 3, i.e. a combustion engine using dihydrogen as fuel. Typically, the powertrain 3 comprises a cylinder head 31 and at least one cylinder in which a movable piston, not shown, is moved. Preferably, the powertrain 3 comprises a plurality of cylinders. According to an embodiment illustrated in Figures 1 to 5, the invention can be applied to a small-displacement vehicle. Alternatively, according to a particular embodiment described below with reference to Figures 6 to 8, the invention can be applied to a large-displacement vehicle 1 or sports car, in particular equipped with a V6-type powertrain 3, i.e., comprising six cylinders arranged in a V configuration formed by two banks of three cylinders.

[0033] Throughout the following description, the terms "upstream," "downstream," "inlet," and "outlet" refer to the direction of fluid flow within a given circuit, as illustrated by arrows. Similarly, the terms "first," "second," "primary," and "secondary" are intended to distinguish similar components and not to define a hierarchy within the present invention.

[0034] In general, the thermal management system 2 according to the invention comprises at least one primary boost circuit 4, suitable for allowing the circulation of a boost air flow FAS, and at least one secondary circuit 5 for circulating a heat transfer fluid FR.

[0035] In the example illustrated in Figures 1 to 5, implemented in a particular vehicle 1, or a "small displacement" type vehicle, the powertrain 3 includes, in particular, four cylinders or fewer. In a known, but not detailed, manner, the charge airflow FAS is intended to be sent to an intake manifold, not shown, of the powertrain 3 in order to be injected into a combustion chamber delimited by at least one cylinder, or, as illustrated, a plurality of combustion chambers, each of said chambers being delimited by one of the cylinders. The charge airflow FAS is then discharged via an exhaust manifold. The at least one primary charge circuit 4 is thus an open circuit passing through the powertrain 3.

[0036] At least one primary circuit 4 allows the circulation and thermal management of the boost air flow FAS. It includes a turbocharger 41, in particular arranged upstream of the powertrain 3 in a direction of flow of the boost air flow FAS, capable of increasing the pressure of the boost air flow FAS.

[0037] The at least one primary circuit 4 further comprises a primary cooling module 42 comprising at least one primary set of controlled flaps 43 and a primary heat exchanger 44 configured to implement heat exchange between the charge airflow FAS and an outside airflow FE at vehicle 1. The primary heat exchanger 44 has, in particular, the function of a charge air cooler, also known as RAS. External airflow FE is understood to mean an airflow coming from the environment outside the vehicle 1 and which can, for example, be brought into the engine compartment of the vehicle 1 from the front, as shown in figures 1 to 5, for example at the level of an external airflow supply grille FE.

[0038] Also, preferably, the primary cooling module 42 includes a primary motor-fan unit 45, also known as GMV, comprising a fan operated by an electric motor.

[0039] At least one secondary circulation circuit 5 is configured to allow the circulation of a heat transfer fluid FR, also referred to as a coolant, such as glycol water. At least one secondary circulation circuit 5 is configured to allow the heat treatment of at least a portion of the powertrain 3. It thus includes the powertrain 3, in particular the cylinder head 31, and allows the passage of the heat transfer fluid FR through at least a portion thereof. Also, at least one secondary circulation circuit 5 includes at least one pump 32.

[0040] The at least one secondary circuit 5 also includes a secondary cooling module 51, comprising a secondary set of controlled flaps 52 and a heat exchanger 53 configured to implement heat exchange between the heat transfer fluid FR and the outside airflow FE to the vehicle 1. The heat exchanger has in particular the function of a radiator, that is to say it is configured so that the heat transfer fluid FR gives up heat to the outside airflow FE, thus enabling the cooling of said fluid and, by extension, of all or part of the components arranged on the at least one secondary circuit 5.

[0041] The at least one secondary circuit 5 is a closed circuit, fluidically independent of the at least one primary circuit 4, so that the heat transfer fluid FR does not mix with the charge airflow FAS or circulate in the at least one primary circuit 4, and vice versa. It should also be noted, as detailed below, that separate portions of the outside airflow FE can exchange heat with the primary heat exchanger 44 and the heat exchanger 53, or alternatively, the same portion of the outside airflow FE can successively pass through the primary heat exchanger 44 and the heat exchanger 53.

[0042] Also, preferably, the secondary cooling module 51 comprises a secondary motor-fan assembly 54 including a fan driven by an electric motor. Alternatively, particularly for a thermal management system 2 arrangement as illustrated in Figures 2 and 3, which is more exposed below, the primary cooling module 42 and the secondary cooling module 51 include a common motor-fan assembly.

[0043] The thermal management system 2 according to the invention further comprises a control means 6 for the primary cooling module 42 and the secondary cooling module 51. Such a control means 6 is particularly capable, at any given moment, of modifying the degree of opening of the primary set of flaps 43 and / or the secondary set of flaps 52 separately, respectively, in order to regulate the flow of outside air FE circulating through the primary heat exchanger 44 and / or the heat exchanger 53, respectively. For each set of controlled flaps considered, the control means 6 is capable of moving all or part of the flaps of said set between a "closed" configuration, preventing or limiting the passage of the outside air FE through at least part of the associated heat exchanger considered, and an "open" configuration.It is understood that the various shutters can also be arranged in an intermediate configuration corresponding to a position between the "open" and "closed" configurations.

[0044] Finally, the thermal management system 2 includes at least one secondary heat exchanger 7 configured to implement heat exchange between the charge airflow FAS circulating in at least one primary circuit 4 and the heat transfer fluid FR circulating in at least one secondary circuit 5. The presence of the secondary heat exchanger 7 advantageously provides a two-stage thermal management system, particularly for cooling, of the charge airflow FAS, while limiting the dimensions and size of the primary heat exchanger 44 in a manner suitable for complying with the space constraints of the vehicle 1 on the one hand, and / or for optimizing the performance of the vehicle 1, for example, in the context of sporting use. Here, "stage" refers to thermal management carried out in two phases, via two distinct heat exchangers, physically separated from each other.

[0045] Indeed, in the case of a hydrogen powertrain 3, the thermal management implemented at the level of the boost circuit, namely here at least one primary circuit 4, is essential to provide the required engine power. Since the temperature of the boost air flow FAS exiting the turbocharger 41, intended to be sent to the intake manifold of the powertrain 3, is too high to ensure such performance, the implementation of two "stages" of thermal management of the boost air flow FAS makes it possible to ensure a desired level of performance while maintaining a suitable size and limiting the dimensions of at least one primary heat exchanger 44.

[0046] Preferably, as illustrated in [Fig. 1], at least one secondary heat exchanger 7 is disposed within at least one primary circuit 4 of circulation, downstream of the turbocharger 41 and upstream of the primary heat exchanger 44, follows a direction of charge air flow FAS. In this way, at least one secondary heat exchanger 7 provides initial thermal treatment, specifically cooling, of the compressed charge air flow FAS exiting the turbocharger 41. The secondary heat exchanger 7 thus implements the first stage of thermal management within the at least one primary circulation circuit 4.

[0047] Additionally or alternatively, at least one secondary heat exchanger 7 is disposed, within the secondary circulation circuit 5, downstream of the powertrain 3, in particular of at least a part of the cylinder head 31 of the powertrain 3, and upstream of at least one heat exchanger 53 in a direction of circulation of the heat transfer fluid FR.

[0048] The "first stage" of thermal management is thus ensured by at least one secondary heat exchanger 7 by implementing indirect heat exchange with the outside airflow FE via at least one secondary circuit 5 for circulating the heat transfer fluid FR. The "second stage" of thermal management, configured to operate after the "first stage" according to the direction of the charge airflow FAS, is implemented by direct heat exchange with the outside airflow FE via at least one secondary heat exchanger 7. Such an arrangement of at least one secondary heat exchanger 7 is particularly suitable in the case of high charge airflow FAS temperatures, since at least one secondary circuit 5 has a better heat exchange capacity in such situations.

[0049] Figures 2 to 5 schematically illustrate various arrangements of at least one heat exchanger 53 and at least one primary heat exchanger 44 within the vehicle 1, and relative to each other. By convention in the following description, the direction in which the vehicle 1 moves in a straight line is defined as the longitudinal direction X, oriented from front to rear. The direction perpendicular to the longitudinal direction and located in a plane parallel to the ground is called the transverse direction Y. The direction perpendicular to the X and Y directions is called the vertical direction Z. Thus, a right-handed coordinate system XYZ is defined, as represented in the figures where necessary.

[0050] According to particular embodiments, illustrated in Figures 2 to 5, at least one secondary cooling module 51 is disposed at the front of the vehicle 1, for example in a front half of the vehicle 1, in particular at the level of the compartment housing the powertrain 3. According to one embodiment, as illustrated in Figures 2 and 3, at least one primary cooling module 42 is disposed upstream of the secondary cooling module 51 of the vehicle 1 according to a direction of external airflow FE. Alternatively, at least one secondary cooling module 51 and at least one primary cooling module 42 may be adjacent, in particular arranged side by side, in the front half of the vehicle as shown in Figures 4 and 5.

[0051] More particularly, according to a first embodiment, illustrated in [Fig. 2] or 3, at least one primary cooling module 42 is at least partially arranged upstream of at least one secondary cooling module 51 in a direction of circulation of the outside air flow FE such that the same portion of the outside air flow FE circulates successively through at least one primary heat exchanger 44 of at least one primary cooling module 42 and then through at least one heat exchanger 53 of at least one secondary cooling module 51. In other words, in such an embodiment, at least one primary set of flaps 43, included in at least one primary cooling module 42, is arranged so as to regulate the circulation of at least a portion of the outside air flow FE intended to circulate successively through at least one primary heat exchanger 44 and then through at least one heat exchanger 53.For example, at least one primary heat exchanger 44 is thus at least partially aligned, along the longitudinal direction X, with at least one heat exchanger 53 such that the same axis parallel to the longitudinal direction passes through said exchangers. Conversely, at least one secondary set of flaps 52 is arranged so as to regulate the circulation of a portion of the airflow intended to circulate only through the heat exchanger 53.

[0052] Alternatively, as illustrated in [Fig.4], at least one primary cooling module 42 and at least one secondary cooling module 51 are arranged so that distinct portions of the outside airflow FE circulate through at least one heat exchanger 53 and at least one primary heat exchanger 44. At least one secondary set of flaps 52, included in at least one secondary cooling module 51, and at least one primary set of flaps 43, included in at least one primary cooling module 42, then allow the circulation of distinct portions of the outside airflow FE to be regulated and, consequently, the heat exchange implemented at at least one heat exchanger 53 and at least one primary heat exchanger 44 to be regulated separately.For example, at least one heat exchanger 53 and at least one primary heat exchanger 44 are offset relative to each other along the transverse direction Y.

[0053] Optionally, the vehicle 1 and / or the thermal management system 2 according to the invention includes at least one primary temperature sensor 46, capable of measuring a temperature of the supercharged airflow FAS at at least one point, and at least one secondary temperature sensor 55 configured to measure a temperature of the heat transfer fluid FR at at least one point.

[0054] For example, at least one primary temperature sensor 46 is located downstream of the turbocharger 41. In particular, preferably, at least one primary temperature sensor 46 is suitable for measuring the temperature of the boost air flow FAS exiting at least one primary heat exchanger 44, for example at the intake manifold of the powertrain 3. Similarly, for example, at least one secondary sensor 55 is located downstream of at least one heat exchanger 53, for example before the entry of the heat transfer fluid FR into the cylinder head 31 of the powertrain 3.

[0055] Thus, according to an example of the operation of the thermal management system 2 as described above, the charge airflow FAS is sent to at least one turbocharger 41 where it is compressed. The outgoing charge airflow FAS has a higher pressure and temperature than at its inlet to the turbocharger 41. The charge airflow FAS is then sent to at least one secondary heat exchanger 7 where heat exchange takes place between said airflow and the heat transfer fluid FR circulating in at least one secondary circuit 5 without them mixing. The heat transfer fluid FR absorbs heat from the charge airflow FAS so that the charge airflow FAS exiting at least one secondary heat exchanger 7 has a lower temperature than the charge airflow FAS entering said exchanger.Conversely, the heat transfer fluid FR exiting at least one secondary heat exchanger 7 has a higher temperature than the incoming fluid.

[0056] The charge airflow FAS is then sent to at least one primary heat exchanger 44. At least one primary set of flaps 43 is configured to be open in a suitable configuration, via the control means 6, according to the thermal cooling requirement of the charge airflow FAS. Similarly, the primary motor-fan assembly 45 is configured to be activated or deactivated, via said control means 6, as required. When it is necessary to cool the charge airflow FAS exiting the secondary heat exchanger 7, for example, at least one primary set of flaps 43 is arranged in an "open" configuration or in an intermediate configuration so that the outside airflow FE to the vehicle 1 flows through at least one primary heat exchanger 44 and absorbs heat from the charge airflow FAS.The FAS supercharge airflow exiting at least one primary heat exchanger 44 is thus cooled to a suitable temperature and can be sent to the powertrain 3.

[0057] Simultaneously, the heat transfer fluid FR exiting at least one secondary heat exchanger 7 is sent to at least one heat exchanger 53. At least one secondary set of flaps 52 is configured to be moved into a suitable configuration according to the thermal cooling requirement of the heat transfer fluid FR via the control means 6. The same applies to the secondary motor-fan assembly 54, which can be activated or not as needed. When it is necessary to cool the heat transfer fluid FR exiting the secondary heat exchanger 7, for example, at least one secondary set of flaps 52 is arranged in an "open" configuration or in an intermediate configuration so that the outside airflow FE to the vehicle 1 flows through at least one heat exchanger 53 and absorbs heat from the heat transfer fluid FR.The heat transfer fluid FR exiting at least one heat exchanger 7 is thus cooled and can be sent to the powertrain 3, particularly to the cylinder head 31, thus enabling its cooling.

[0058] As illustrated in Figures 6 to 8, the management system according to the invention can also be extended to sports vehicles or vehicles of the "large displacement" type. In the illustrated example, the powertrain 3 is, for example, of the "V6" type and comprises six cylinders arranged in a "V".

[0059] In such an embodiment, the thermal management system 2 according to the invention comprises: - a plurality of primary supercharging circuits 4, each being capable of allowing the circulation of a specific supercharging airflow FAS and each of said circuits comprising a turbocharger 41, a primary cooling module 42 comprising a primary set of controlled flaps 43 and a primary heat exchanger 44 configured to implement heat exchange between the specific supercharging airflow FAS of said circuit and an external airflow FE to the vehicle 1 as described above; - a plurality of secondary circuits 5 for circulating a heat transfer fluid FR, independent of each other, each being connected to the powertrain 3 and comprising a secondary cooling module 51 including a secondary set of flaps 52 and a heat exchanger 53 configured to implement heat exchange between the heat transfer fluid FR and the external airflow FE to the vehicle 1.

[0060] In such an embodiment, the thermal management system 2 further comprises a plurality of secondary heat exchangers 7, each configured to implement heat exchange between the boost airflow FAS circulating in one of the primary circuits 4 and the heat transfer fluid FR circulating in one of the secondary circuits 5.

[0061] The preceding description, made with reference to a thermal management system 2 comprising a single primary boost circuit 4 and a single secondary heat transfer fluid circuit 5 FR, applies here mutatis mutandis. It should be noted that, in the following, the at least one primary circuit 4, the at least one secondary circuit 5, and the various components described above will be preceded by "first" so as to distinguish them from a "second" component or circuit of the same type. The present thermal management system 2 generally comprises, unless otherwise specified, a duplication of the primary circuit 4 and secondary circuit 5 described above, so as to include two circuits of each type with separate operations.

[0062] In more detail, the thermal management system 2 illustrated in Figures 6 to 8 comprises a primary boost circuit 4, hereinafter referred to as the first primary boost circuit 4a, configured to allow the circulation of a first boost airflow FAS1 and comprising a first turbocharger 41a, a first primary cooling module 42a comprising a first primary set of flaps 43a and a first primary heat exchanger 44a. The system also comprises at least one secondary circuit 5 for circulating heat transfer fluid FR, hereinafter referred to as the first secondary circuit 5a, comprising a portion of the powertrain 3, a first secondary cooling module 51a, comprising a first secondary set of flaps 52a and a first heat exchanger 53a.

[0063] The thermal management system 2 further comprises, a second primary boost circuit 4b configured to allow the circulation of a second boost airflow FAS2 and comprising a second turbocharger 41b, a second primary cooling module 42b comprising a second primary set of flaps 43b and a second primary heat exchanger 44b configured to implement heat exchange between the boost airflow FAS circulating in said second primary circuit 4b and an external airflow FE to the vehicle 1. The system also comprises, a second secondary heat transfer fluid circulation circuit 5b FR, comprising a portion of the powertrain 3, a second secondary cooling module 51b, comprising a second secondary set of flaps 52b and a second heat exchanger 53b.

[0064] Note that the second primary boost circuit 4b may be identical to or different from the first primary boost circuit 4a. Preferably, said circuits have a similar architecture. The same applies to the first secondary circulation circuit 5a and the second secondary circulation circuit 5b.

[0065] The thermal management system 2 also includes at least one secondary heat exchanger 7, referred to as the first secondary heat exchanger 7a, configured to implement heat exchange between the airflow of The supercharging air FAS1 circulates in the first primary circuit 4a and the heat transfer fluid FR circulates in the first secondary circuit 5a. The thermal management system 2 finally includes a second secondary heat exchanger 7b, configured to implement a heat exchange between the supercharging airflow FAS2 circulating in the second primary circuit 4b and the heat transfer fluid FR circulating in the second secondary circuit 5b.

[0066] Additionally, the thermal management system 2 includes at least one pump 32. According to a preferred embodiment, illustrated, the system includes a pump 32 common to the first secondary circuit 5a and the second secondary circuit 5b for circulating the heat transfer fluid FR in order to limit the size and cost of the system. Alternatively, each of the secondary circuits may include its own pump 32.

[0067] Also, each of the primary circuits 4 and secondary circuits 5 can respectively include primary temperature sensors 46, secondary temperature sensors 55, primary motor-fan assemblies 45 and / or secondary motor-fan assemblies 54 as described above.

[0068] Preferably, the first heat exchanger 53a and the second heat exchanger 53b are arranged in the front half of the vehicle, in particular at the front of vehicle 1, while the first primary heat exchanger 44a and the second primary heat exchanger 44b are arranged in a rear half of vehicle 1. For example, the first heat exchanger 53a and the first primary heat exchanger 44a are arranged on a right side of vehicle 1 while the second heat exchanger 53b and the second primary heat exchanger 44b are arranged on a left side of vehicle 1, as shown in [Fig. 7] or 8. Note that the second primary cooling module 42b is not shown in [Fig. 8] for the sake of clarity.

[0069] The invention also relates to a thermal management method 100 of the vehicle 1 automobile. In other words, such a method can be considered a method of operating or using a vehicle 1 equipped with the thermal management system 2 according to the invention. Alternatively, such a method corresponds to a method of operating or using the thermal management system 2. Such a method can be applied to a thermal management system 2 as defined in Figures 1 to 5, comprising a single primary circulation circuit 4 and a single secondary circulation circuit 5, here implemented in a small-displacement vehicle, or to a thermal management system 2 as defined in Figures 6 to 8, comprising a plurality of primary circuits 4 and secondary circuits 5. In the latter case, the method according to the invention is applied mutatis mutandis, separately, to each pair of a primary circulation circuit 4 and a secondary circulation circuit 5. operating together and configured to implement heat exchange via the secondary heat exchanger 7 which they comprise and at least one control means 6 or a plurality of control means 6.

[0070] Figures 9 and 10 illustrate examples of flowcharts separating the processing of information relating to at least one primary circuit 4 and at least one secondary circuit 5 from the actions associated with such information. Figure 9 illustrates a portion of the process implemented with respect to at least one primary circuit 4, while Figure 10 illustrates a portion of the process implemented with respect to at least one secondary circuit 5. This separation is made simply for the sake of clarity. It is understood, however, that the process according to the invention considers the entire thermal management system, namely each of the circuits it comprises, simultaneously or successively.

[0071] In general, the method according to the invention comprises a measurement step E01 of a temperature T_FAS of the charge airflow FAS and a temperature T_FR of the heat transfer fluid FR via at least one primary temperature sensor 46 and at least one secondary temperature sensor 55, respectively. Such measurements can be performed at regular time intervals or in real time. In particular, as described above, the temperature T_FAS of the charge airflow FAS is measured at the intake manifold of the powertrain 3 or at its inlet. In particular, as described above, the temperature T_FR of the heat transfer fluid FR is measured at the inlet of the cylinder head 31 of the powertrain 3.

[0072] The method then includes a step E02 for determining a thermal management mode to be applied based on the measured temperatures. Here, "thermal management mode" refers both to a type of heat treatment, such as whether or not cooling is required, and to the level or intensity of such heat treatment. For example, such a determination can be made by comparing temperature measurement data relating to the charge airflow FAS with at least one predefined primary temperature threshold S_FAS and / or by comparing temperature measurement data relating to the heat transfer fluid FR with at least one secondary temperature threshold S_FR. Such threshold values ​​can be stored on one or more memory elements of the vehicle 1, while the comparisons can be performed by a processing unit comprising a control unit or an on-board computer.

[0073] The method then includes an application step E03 of the thermal management mode determined by adjusting the degree of opening of at least one primary set of dampers 43 and / or at least one secondary set of dampers 52 via the control means 6. As previously explained, at least one primary set of shutters 43 and at least one secondary set of shutters 52 can each be arranged in an "open", "closed" or intermediate configuration, independently of each other.

[0074] In particular, at least one primary set of flaps 43 is moved to its "open" configuration when the temperature T_FAS of the charge airflow FAS is greater than or equal to a first primary temperature threshold S_FAS1, as indicated by mode E031a. For example, the first primary temperature threshold S_FAS1 is on the order of 150°C.

[0075] In this way, when a heating of the charge airflow FAS to a temperature greater than or equal to the first primary temperature threshold S_FAS1 is detected, i.e. when the cooling carried out at the secondary heat exchanger 7 is not sufficient, additional cooling of the charge airflow FAS is implemented at the level of at least one primary heat exchanger 44, as described previously, so that the charge airflow FAS gives up heat to the outside airflow FE circulating through at least one primary heat exchanger 44 and at least one primary set of open flaps 43.

[0076] Conversely, when no heating of the airflow is observed, i.e., when the temperature T_FAS of the boost airflow FAS is strictly below the first primary temperature threshold S_FAS1, at least one primary set of flaps 43 is arranged in the "closed" configuration since it is not necessary to implement heat exchange, as represented in [Fig. 7] by mode E030a. In this way, the aerodynamics of vehicle 1 are optimized and internal drag is reduced when heat treatment of the boost airflow FAS is not required.

[0077] Additionally or alternatively, at least one secondary set of flaps 52 is moved to its "open" configuration, represented in [Fig. 10] by mode E032a, when the temperature T_FR of the heat transfer fluid FR is greater than or equal to a first secondary temperature threshold S_FR1. For example, the first secondary temperature threshold S_FR1 is on the order of 90°C.

[0078] Thus, when a heating of the heat transfer fluid FR to a temperature greater than or equal to the first secondary temperature threshold S_FR1 is detected, a cooling of said fluid is implemented at the level of at least one heat exchanger 53, as described previously, so that the heat transfer fluid FR gives up heat to the outside air flow FE circulating through at least one heat exchanger 53 and at least one secondary set of flaps 52, open.

[0079] Conversely, when no heating of said fluid is observed, that is to say when the temperature T_FR of the heat transfer fluid FR is strictly below the first threshold secondary temperature S_FR1, at least one secondary set of flaps 52 is arranged in the "closed" configuration, represented by mode E030b, since it is not necessary to implement heat exchange.

[0080] Optionally, the application step E03 of the thermal management mode may include adjusting an operating mode of the primary fan motor assembly 45 of at least one primary cooling module 42 when the temperature T_FAS of the charge airflow FAS is greater than or equal to a second primary temperature threshold S_FAS2, which is higher than the first primary temperature threshold S_FAS1, represented by mode E031b. For example, the second primary temperature threshold S_FAS2 is strictly greater than 150°C and less than or equal to 170°C, in particular, it is on the order of 160°C.

[0081] Thus, for example, when the temperature T_FAS of the charge airflow FAS is greater than or equal to the first primary temperature threshold S_FAS1 and strictly less than the second primary threshold, the primary set of flaps 43 is placed in the "open" configuration while the fan motor assembly can be switched off, here forming mode E031a. When the temperature T_FAS of the charge airflow FAS is greater than or equal to the second primary temperature threshold S_FAS2, the control means 6 can activate the primary fan motor assembly 45, thus forming mode E031b. Such a principle advantageously optimizes the heat exchange implemented at the primary heat exchanger 44.Optionally, the primary motor-fan unit 45 can be controlled to implement an outside airflow FE passing through at least one primary heat exchanger 44, more or less significant depending on the measured temperature exceeding the second primary temperature threshold S_FAS2 and / or depending on a longitudinal speed of the vehicle 1.

[0082] A similar principle applies mutatis mutandis to the secondary motor-fan assembly 54, the method according to the invention then comprising adjusting an operating mode of said motor-fan assembly when the temperature T_FR of the heat transfer fluid FR is greater than or equal to a second secondary temperature threshold S_FR2, which is higher than the first secondary temperature threshold S_FR1, here represented by mode E032b. Thus, when the temperature T_FR of the heat transfer fluid FR is greater than or equal to the first secondary temperature threshold S_FR1 and strictly less than the second secondary temperature threshold S_FR2, the primary set of dampers 43 is placed in the "open" configuration and the motor-fan assembly is switched off. Conversely, when the temperature T_FR of the heat transfer fluid FR is greater than or equal to the second secondary temperature threshold S_FR2.For example, the second secondary temperature threshold S_FR2 is around 105°C.

[0083] Optionally, the application step E03 of the thermal management mode may include the limitation E031c of the torque of the powertrain 3 when the temperature T_FAS of the measured charge airflow FAS is greater than or equal to a third primary temperature threshold S_FAS3, strictly greater than the first primary temperature threshold S_FAS1 and the second primary temperature threshold S_FAS2. For example, the third primary temperature threshold S_FAS3 is on the order of 200°C.

[0084] In particular, when the charge airflow (FAS) requires cooling, especially when the measured charge airflow temperature (T_FAS) is greater than or equal to the third primary temperature threshold (S_FAS3), but no cooling of the heat transfer fluid is required because the fluid temperature (T_FR) is strictly below the first secondary temperature threshold (S_FR1), the method can be configured to implement the E031c torque limitation of the powertrain 3. This principle is particularly relevant under high torque demand in cold conditions. Such torque limitation is implemented to ensure that at least one primary boost circuit (4) responds more quickly than the powertrain 3 reaches operating temperature.

[0085] The present invention thus advantageously proposes a thermal management system and method for a hydrogen-powered vehicle, ensuring optimized two-stage thermal regulation. This limits the increased bulk at the front compared to prior art systems and reduces the aerodynamic impact of said system on vehicle performance. The thermal management system according to the invention also advantageously allows, by virtue of its two-stage thermal treatment architecture and the specific arrangement of controlled flap assemblies, the modulation of the use of the various heat exchangers according to engine load conditions, thereby optimizing power distribution within the vehicle and maintaining a better energy balance.The present invention thus advantageously enables the implementation of different control strategies for said flaps, and consequently for the thermal management system, making it possible to meet the varied needs of the vehicle.

[0086] The present invention cannot, however, be limited to the means and configurations described and illustrated herein and it also extends to any equivalent means or configuration and to any technically operative combination of such means insofar as they ultimately fulfill the functionalities described and illustrated in this document.

Claims

Demands

1. Thermal management system (2) of a motor vehicle (1) equipped with a hydrogen powertrain (3), the thermal management system (2) comprising: - at least one primary boost circuit (4) capable of permitting the circulation of a boost airflow (FAS), said circuit comprising a turbocharger (41), a primary cooling module (42) comprising a primary set of controlled flaps (43) and a primary heat exchanger (44) configured to implement heat exchange between the boost airflow (FAS) and an external airflow (FE) to the vehicle (1);- at least one secondary circuit (5) for circulating a heat transfer fluid (RF) comprising a hydrogen powertrain (3) and a secondary cooling module (51) comprising a secondary set of controlled flaps (52) and a heat exchanger (53) configured to implement heat exchange between the heat transfer fluid (RF) and the external airflow (EF) to the vehicle (1); the system further comprising a control means (6) for the primary set of flaps (43) and the secondary set of flaps (52) and at least one secondary heat exchanger (7) configured to implement heat exchange between the charge airflow (FAS) circulating in at least one primary circuit (4) and the heat transfer fluid (RF) circulating in at least one secondary circuit (5);characterized in that at least one secondary heat exchanger (7) is disposed downstream of the turbocharger (41) and upstream of the primary heat exchanger (44) in a direction of charge air flow (FAS) and in that at least one secondary heat exchanger (7) is disposed downstream of the powertrain (3) and upstream of at least one heat exchanger (53) in a direction of heat transfer fluid flow (FR).;

2. Thermal management system (2) according to the preceding claim, wherein at least one primary cooling module (42) is at least partially disposed upstream of at least one secondary cooling module (51) in a direction of flow of the outside air flow (FE), the primary set of flaps (43) being arranged so as to regulate the circulation of at least a part of the outside air flow (FE) intended to circulate successively through the primary heat exchanger (44) and then the heat exchanger (53).

3. Thermal management system (2) according to any one of the preceding claims, comprising: - a plurality of primary boost circuits (4, 4a, 4b), each being capable of allowing the circulation of a boost airflow (FAS, FAS1, FAS2) specific to it and each of said circuits comprising a turbocharger (41, 41a, 41b), a primary cooling module (42, 42a, 42b) comprising a primary set of flaps (43, 43a, 43b) and a primary heat exchanger (44, 44a, 44b) configured to implement heat exchange between the boost airflow (FAS, FAS1, FAS2) specific to said circuit and an external airflow (FE) to the vehicle (1);- a plurality of secondary circuits (5, 5a, 5b) for circulating a heat transfer fluid (FR), each comprising at least a part of the powertrain (3) and a secondary cooling module (51, 51a, 51b) comprising a secondary set of flaps (52, 52a, 52b) and a heat exchanger (53, 53a, 53b) configured to implement heat exchange between the heat transfer fluid (FR) and the external airflow (FE) to the vehicle (1); the system further comprising a plurality of secondary heat exchangers (7, 7a, 7b), each configured to implement heat exchange between the charge airflow (FAS, FAS1, FAS2) circulating in one of the primary circuits (4, 4a, 4b) and the heat transfer fluid (FR) circulating in one of the secondary circuits (5, 5a, 5b).

4. Thermal management system (2) according to the preceding claim, comprising at least one pump (32) arranged so as to be common to the plurality of secondary circuits (5, 5a, 5b) for circulating a heat transfer fluid (FR).

5. Motor vehicle (1) comprising a thermal management system (2) according to any one of the preceding claims.

6. A method for thermal management (100) of a motor vehicle (1) according to the preceding claim, the vehicle (1) being equipped with

7. less a primary temperature sensor (46), capable of measuring a temperature (T_FAS) of the supercharging airflow (FAS) at at least one point of at least one primary circuit (4), and a secondary temperature sensor (55) configured to measure a temperature (T_FR) of the heat transfer fluid (FR) at at least one point of at least one secondary circuit (5), the method comprising: - a measurement step (E01) of a temperature (T_FAS) of the supercharging airflow (FAS) and of the heat transfer fluid (FR) via the primary temperature sensor (46) and the secondary temperature sensor (55) respectively; - a determination step (E02) of a thermal management mode to be applied according to the measured temperatures; - an application step (E03) of the thermal management mode determined by adjusting a degree of opening of at least the primary set of flaps (43) and / or the secondary set of flaps (52) by means of the control means (6), the primary set of flaps (43) being open when the temperature (T_FAS) of the charge air flow (FAS) is greater than or equal to a first primary temperature threshold (S_FAS1) and / or the secondary set of flaps (52) being open when the temperature (T_FR) of the heat transfer fluid (FR) is greater than or equal to a first secondary temperature threshold (S_FR1). Thermal management method (100) according to the preceding claim, wherein at least one primary cooling module (42) comprises a primary motor-fan assembly (45) and at least one secondary cooling module (51) comprises a secondary motor-fan assembly (54), the application step (E03) of the thermal management mode comprising adjusting an operating mode of the primary motor-fan assembly (45) when the temperature (T_FAS) of the charge airflow (FAS) is greater than or equal to a second primary temperature threshold (S_FAS2), greater than the first primary temperature threshold (S_FAS1), and / or adjusting an operating mode of the secondary motor-fan assembly (54) when the temperature (T_FR) of the heat transfer fluid (FR) is greater than or equal to a second secondary temperature threshold (S_FR2), greater than the first secondary temperature threshold (S_FR1).

8. Method of thermal management (100) of a motor vehicle (1) according to the preceding claim, wherein the application step E03 of the thermal management mode includes limiting the torque of the powertrain (3) when the temperature (T_FAS) of the charge airflow (FAS) is greater than or equal to a third primary temperature threshold (S_FAS3).

9. Product computer program comprising program code instructions recorded on a computer-readable medium to implement the steps of the thermal management process (100) according to any one of claims 6 to 8 when said program is running on a computer.

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