GB2519867A

GB2519867A - Heat exchanger device for a motor vehicle as well as a motor vehicle

Info

Publication number: GB2519867A
Application number: GB1418705.8A
Authority: GB
Inventors: Ray Ayala; Dinesh Madugundi; Donald Vena; Rafael Dos Santos; Michael Gatza; Michael Norlin; Georgeanna Alemany
Original assignee: Daimler AG
Current assignee: Mercedes Benz Group AG
Priority date: 2014-10-21
Filing date: 2014-10-21
Publication date: 2015-05-06
Also published as: GB201418705D0

Abstract

A heat exchanger device (10) for a motor vehicle (110), the heat exchanger device (10) comprising: at least one air inlet element (30) capable of directing an air flow (70) to at least one heat exchanger bank (20) of the heat exchanger device (10), which is arranged in front of a wheel well (50) of a wheel (52) according to the longitudinal direction (100) of the motor vehicle (110); and an air guiding device (40) capable of directing the air flow (70) passing the heat exchanger device (10) around the wheel (52), wherein at least one air inlet (54) in a front portion (56) of the wheel well (50), the air inlet (54) being capable of directing the air flow (70) into the wheel well (50), and at least one guiding element (42) of the air guiding device (40), the guiding element (42) being arranged at the air inlet (54) and the guiding element (42) being capable of guiding the air flow (70) along an inner surface (58) of the wheel (52) in the wheel well (50).

Description

Heat Exchanger Device for a Motor Vehicle as well as a Motor Vehicle The invention relates to a heat exchanger device according to the preamble of patent claim 1 as well as a motor vehicle.

Heat exchangers or heat exchanger devices are widely-used in motor vehicles. Such heat exchanger devices allow the heat transfer between different kinds of fluids such as ambient air, coolant and motor oil to name only a few. Most of the common motor vehicles comprise a primary heat exchanger device, which is arranged at a front end of a respective motor vehicle and which is usually arranged adjacent to and behind a grille according to a forward driving direction of the motor vehicle. In other words the grille is arranged in front of at least one primary heat exchanger device wherein the grille can provide an air flow of ambient air so that the air can flow against and around the primary heat exchanger device in order to exchange heat with a fluid or a medium such as e.g. a coolant or a motor oil. The heat exchanger device usually also comprises a fan capable of accelerating the air flow towards the heat exchanger in order to influence the heat transfer and to uncouple the transfer at least partially from the head wind. In other words, by means of the fan also at low head wind (due to low vehicle speed and additionally or alternatively due to low wind speed) a sufficient cooling can be achieved.

US 6230832 Bi shows a motor vehicle which is designed as a truck and which comprises a primary heat exchanger device which is arranged behind a grille of the truck according to the longitudinal direction of the truck or according to its forward driving direction, respectively. The primary heat exchanger device comprises a radiator wherein air passing through the radiator flows through an engine compartment of the truck and into cowl openings which are arranged at the sides of the vehicle. Due to guiding the air through the engine compartment and through the cowl openings and, thus, along the truck the aerodynamic drag of the truck is particularly low since turbulence of the air passing through the engine compartment and the cowl openings can be prevented very efficiently.

However, the full potential of cooling by means of the head wind is not tapped completely.

DE 10 2008 022 554 Al shows a front section of a motor vehicle. The front section comprises a primary heat exchanger device which is arranged in the middle of a front end of the front section. The front section also comprises two further heat exchanger devices which are laterally offset compared to the heat exchanger device. The primary heat exchanger device and the thereto laterally arranged heat exchanger devices are connected by means of an air duct which can be flowed through by ambient air. The air duct comprises a locking device by means of which the air flow from a front end air inlet towards the laterally arranged heat exchanger devices can be disabled in dependency on the driving speed of a motor vehicle which comprises such a front section. Due to the use of several heat exchanger devices each comprising a heat exchanger bank which can consist of one or more heat exchangers, the heat dissipation is particularly enhanced, especially in comparison with vehicles comprising only one primary heat exchanger device. However the aerodynamic drag deteriorates due to unfavourable air guidance.

It is an object of the present invention to provide a heat exchanger device of the aforementioned kind, by means of which both a particularly effective cooling performance and low aerodynamic drag is achieved.

This object is solved by a heat exchanger device having the features of patent claim 1.

Advantageous embodiments with expedient and non-trivial developments of the invention are indicated in the other patent claims.

It is a further object of the present invention to provide a motor vehicle having particularly low aerodynamic drag and an effective cooling performance.

This object is solved by a motor vehicle having the features of patent claim 8.

In order to provide a heat exchanger device of the kind indicated in the preamble of patent claim 1, by means of which both an effective cooling performance and low aerodynamic drag can be achieved, according to the present invention at least one air inlet is arranged in a front portion of the wheel well, the air inlet being capable of directing the air flow into the wheel well and at least one guiding element of the air guiding device is arranged at the air inlet and the guiding element being capable of guiding the air flow along an inner surface of the wheel in the wheel well.

In other words the heat exchanger device comprises at least one air inlet which is designed as an opening and by means of which the air flow is directed into the wheel well.

In order to achieve particularly low aerodynamic drag the heat exchanger device or the air guiding device of the heat exchanger device, respectively, comprises the at least one guiding element which is arranged at the air inlet wherein by means of the guiding element the air flow can be directed along the inner surface of the wheel in the wheel well.

The guiding of the air flow along the inner surface of the wheel in the wheel well is accompanied by two positive effects. On the one hand, since the air flow is directed between the inner surface of the wheel and a surface of the wheel well facing the inner surfacing of the wheel the air flow can circulate around the break system of the motor vehicle or the brake disks and additionally or alternatively the brake pads respectively. In other words the brakes can be cooled by means of the air flow in an especially effective manner. On the other hand due to guiding the air flow between the inner surface of the wheel and the surface of the wheel well facing the inner surface of the wheel the development of eddies can be avoided in an especially effective manner and thereby the aerodynamic drag is kept to a particularly low level. The aerodynamic drag of the motor vehicle would increase significantly if the air flow would be directed towards the rolling surface of the wheels or the tires respectively or if the air flow would be directed in such a manner that the air flow would flow out of the wheel well laterally.

In other words the heat exchanger device comprises the at least one air inlet element by means of which the air flow can be directed towards the at least one heat exchanger bank which can consist of one or more heat exchangers in order to achieve a heat transfer between the air flow and a fluid or a medium in the heat exchanger bank wherein the air flow is directed towards the wheel well or around the wheel respectively by means of the air guiding device. By means of the at least one guiding element which can be designed e.g. as an air deflector, the air flow is guided between the inner surface of the wheel and the surface of the wheel well facing the inner surface of the wheel.

The invention also relates to a motor vehicle comprising a heat exchanger device according to the invention. Advantageous embodiments of the heat exchanger device according to the present invention are to be regarded as advantageous embodiments of the motor vehicle according to the present invention and vice versa.

The advantages offered by the invention are both increased cooling efficiency and particularly low aerodynamic drag.

Further advantages, features, and details of the invention derive from the following description of a preferred embodiment as well as from the drawings. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and/or shown in the figures alone can be employed not only in the respective indicated combination but also in any other combination or taken alone without leaving the scope of the invention.

The drawings show in: Fig. 1 a side view of a front portion of a motor vehicle wherein an air inlet element of a heat exchanger device is arranged in front of a wheel well of the motor vehicle according to a longitudinal direction of the motor vehicle; Fig. 2 a detailed view of the heat exchanger device which is arranged laterally offset relative to a primary heat exchanger device of the motor vehicle; Fig. 3 a perspective rear view of the heat exchanger device; Fig. 4a another side view of the front portion of the motor vehicle according to Fig. 1 wherein an air flow through the heat exchanger device is schematically illustrated; Fig. 4b a sectional view according to a section line A-A in Fig. 4a showing the air flow which is guided by means of a guiding element of the air guiding device; Fig. 5a an exploded view of several parts of the heat exchanger device; and Fig. 5b an isometric view on the heat exchanger device.

Fig. 1 shows a front section of a motor vehicle 110 wherein merely a few parts of the motor vehicle 110 are illustrated. The front section of the motor vehicle 110 comprises a hood 84 which is covering e.g. a motor (not shown) of the motor vehicle 110.

The front section of the motor vehicle 110 also comprises a grille 82 which is arranged at the front end of the motor vehicle and adjacent to the hood 84. The grille 82 is arranged in front of a primary heat exchanger device 80 (not shown in Fig. 1) according to a longitudinal direction 100 which corresponds to a forward driving direction of the motor vehicle 110. The motor vehicle 110 also comprises a heat exchanger device 10 with an air inlet element 30, wherein the heat exchanger device 10 is arranged in front of a wheel well 50 of a wheel 52 according to the longitudinal direction 100 of the motor vehicle 110.

The wheel 52 is not shown in Fig. 1. In conjunction with Fig. 2 it is cognizable that the heat exchanger device 10 is arranged beside the primary heat exchanger device 80 of the motor vehicle 110 according to the cross direction 90 of the motor vehicle 110. The primary heat exchanger device 80 is arranged adjacent to the grille 82 of the motor vehicle 110 according to the longitudinal direction 100. For a better understanding the grille 82 is not shown in Fig. 2, whereby the primary heat exchanger device 80 is at least partially visible. Fig. 2 shows that the air inlet element 30 comprises an inlet duct 32 with a forward-facing inlet opening 34 according to the longitudinal direction 100 of the motor vehicle 110 wherein the inlet opening 34 (in conjunction with the shape and inner contour of the inlet duct 32) is capable of directing ambient air through the heat exchanger device 10. The heat exchanger device 10 also comprises an air inlet 54 in a front portion 56 of the wheel well 50. This air inlet 54 is capable of directing the air flow 70, which is entering the inlet duct 32 through the inlet opening 34, into the wheel well 50.

In conjunction with Fig. 3 it is cognizable that the heat exchanger device 10 also comprises afan 12 which is arranged in a fan shroud 14. The fan 12 and, thus, the fan shroud 14 are arranged between the wheel well 50 and the inlet duct 32 at present.

Fig. 4a in conjunction with 4b, show that the heat exchanger device 10 can be used for both efficient cooling of the motor vehicle 110 and for achieving particularly low aerodynamic drag. Fig. 4b shows across-section of the heat exchanger device 10, the wheel well 50, the wheel 52 and a chassis fairing 72 as well as a chassis fairing vent 74.

Fig. 4b shows that heat exchanger device 10 comprises a heat exchanger bank 20 which is arranged between the fan 12 and the inlet duct 32 of the heat exchanger device 10.

The fan 12 is configured to convey the air flow 70 of ambient air towards the heat exchanger bank 20 of the heat exchanger device 10. The heat exchanger bank 20 presently comprises one heat exchanger but it is clear, that the heat exchanger bank 20 could also comprise more than one heat exchanger. When the motor vehicle 110 is driving according to the longitudinal direction 100 (according to the forward driving direction) the air flow 70 of ambient air flows through the air inlet element 30 and the inlet duct 32 respectively, along the surface of the heat exchanger bank 20 and along the fan 12 (and the fan shroud 14 respectively) towards the front portion 56 of the wheel well 50.

In order to provide a particularly low aerodynamic drag in addition to the enhanced cooling efficiency, the heat exchanger device 10 also comprises an air guiding device 40 with at least one guiding element 42. In other words the air guiding device 40 comprises both a housing portion (not shown) and the guiding element 42, wherein the air guiding device 40 and the guiding element 42 respectively are arranged at the air inlet 54. The guiding element 42 is capable of guiding the air flow 70 along an inner surface 58 of the wheel 52 in the wheel well 50. The wheel well 50 also comprises a separative element 88 which separates the heat exchanger device 10 from the primary heat exchanger device and, thus, the air flow 70 through the heat exchanger device 10 from the air flow through the primary heat exchanger device 80. In this case the separative element 88 is designed as an inner surface of the wheel well 50 facing the inner surface 58 of the wheel 52. In other words by means of the guiding element 42 the air flow 70 is guided between the inner surface 58 and the separative element 88 wherein the air flow 70 is directed through both the chassis fairing vent 74 and the chassis fairing 72 as soon as the air flow flows out of the wheel well 50. By means of the guiding element 42 the air flow 70 is also directed around the front axle 112 of the motor vehicle 110 and, thus, around a brake element (not shown) of the motor vehicle 110. Due to the direction of the air flow 70 around the brake element the brake can be additionally cooled by means of the air flow 70.

It is clear that the primary heat exchanger device 80 comprises a primary heat exchanger bank and at least one primary fan which is configured to convey ambient air towards the primary heat exchanger 80.

Fig. 5a and Fig. Sb show an exploded view and an assembly of the heat exchanger device 10 respectively. Fig. Sa shows the heat exchanger device 10 without the heat exchanger bank 20 and without the fan 12 and, thus, Fig. 5a shows only some of the parts of the heat exchanger device 10. Especially in Fig. 5a it is cognizable that the guiding element 42 of the air guiding device 40 is designed as a louver.

In summary it can be said that by means of the heat exchanger device 10 the aerodynamic efficiency of the motor vehicle 110 can be improved significantly. The usage of the heat exchanger device 10 as part of the motor vehicle 110 allows the motor vehicles 110 exterior to retain the same basic layout as a traditional motor vehicle 110 of the same kind (e.g. a heavy duty truck) and, thus, the same terms can be used to refer to the motor vehicle's 110 body panels. In order to meet increased cooling requirements as well as to achieve particularly high aerodynamic efficiency, in addition to the primary heat exchanger device 80 at least the heat exchanger device 10 can be employed, wherein the heat exchanger device 10 can be arranged at e.g. both sides of the primary heat exchanger device 80 according to the cross direction 90. Thus, the motor vehicle 110 can employ the heat exchanger bank 20 on each side of the primary heat exchanger device 80 wherein the heat exchanger banks 20 are arranged underneath the hood 84 although they are not directly attached to the hood 84. Each of the heat exchanger banks 20 can, thus, be located symmetrically outboard of the primary heat exchanger device 80. The purpose of the heat exchanger banks 20 is to provide additional cooling for the motor vehicle's 110 power train, electrical and climate control systems. The hood 84 of the motor vehicle 110 is engineered as one assembly wherein it is responsible for performing multiple functions integral to the motor vehicle's operation. The hood 84 is comprised of highly engineered external and interior surfaces that are assembled together to form one integrated hood assembly. The hood 84 is engineered to manage both internal and external air flows around and within the motor vehicles 110 exterior surface to optimize both aerodynamic and cooling system performance.

The exterior of the hood 84 is engineered with a priority placed on aerodynamic and cooling system air flow optimization. Thus, the hood's 84 external surface is engineered to aerodynamically guide the external air flow over and around its external surface as well as to guide it into multiple air flow inlets (such as the inlet duct 32) which are engineered into the hood 84. The forward most, leading surface of the hood 84 guides the oncoming air flow 70 both up and over its surface onto the upper surface of the hood 84 as well as around and to the sides of its surface onto the side surfaces of the hood 84. Additionally, the leading surface of the hood 84 guides the oncoming air flow 70 in the hood's 84 system of cooling air flow inlets. The hood 84 is engineered with an air inlet centrally located on its forward, leading surface that provides air flow to the primary bank of heat exchangers (to the primary heat exchanger device 80). This air inlet positively mates with ducting that feeds air to the primary heat exchanger device 80.

The hood 84 is engineered with the two air inlet elements 30 located symmetrically outboard of the primary heat exchanger device 80 on its forward, leading surface. This air inlet element 30 positively mates with ducts that feed air to the heat exchanger banks 20 (which are also arranged symmetrically). Due to optimal inlet placement within high pressure zones and the aforementioned localized geometry of the hood 84, the air flow 70 into the hood's 84 system of inlets and intakes provides these inlets' dependent heat exchangers and air cleaner assembly with the required amount of air flow 70 necessary while minimizing the air inlets' negative influence on the hood's 84 aerodynamics. The interior surface of the hood 84 is engineered with an emphasis placed on underhood air flow and interfacing with the ducting of the primary heat exchanger device 80 and the heat exchanger device 10. The hood's 84 interior surface is engineered to positively mate, when closed, with the primary heat exchanger devices 80 and heat exchanger devices 10 systems' underhood ducting. This allows the air that flows through the inlets in the hood's 84 exterior to continue to the primary heat exchanger device 80 and the heat exchanger devices 10 uninterrupted, and without aerodynamic disturbance. The heat exchanger banks 20 are packaged within an assembly that consist of (in order from forward to rearward and, thus, in opposite direction of the longitudinal direction 100): -a highly engineered inlet duct 32 that positively interfaces the hood-mounted inlet opening 34 via a gasket/seal on its forward side and the heat exchanger bank 20 to which it supplies the air flow 70 in its rearward side. This inlet duct 32 carries air that has flowed through the hood-mounted inlet opening 34 to the heat exchanger bank 20.

-The heat exchanger bank 20, which is an assembly made up of individual heat exchangers.

-The highly engineered fan shroud 14 that positively interfaces on its forward side with the heat exchanger bank 20 and on its rearward side with a cooling air flow exit duct (air inlet 54). The fan shroud 14 provides mounting for an electric fan 12 that provides the air flow 70 upon demand for the cooling system.

-The electric fan 12 that provides the air flow 70 upon demand for the cooling system.

-The highly engineered air inlet 54 which corresponds to an air flow exit duct, that positively interfaces on its forward side with the fan shroud 14 and acts as a part of the wheel liner assembly on its rearward side. This air inlet 54 (the air flow exit duct) directs the air flow 70 from the heat exchanger bank 20 rearwards and allows it to exit through the guiding elements 42 (which is designed as a set of louvers) into the motor vehicle's 110 steer wheel well 50. The wheel well 50 is the area around the steer wheel 52 and tire assembly, beneath the hood 84 and in front of the chassis fairing 72).

-The guiding elements 42 (the set of louvers) that is located at the termination of the exit duct (air inlet 54 at the front portion 56 of the wheel well 50) which guides the air flow 70 as it leaves the air inlet 54 (the exit duct). The purpose of the louvers is to change the direction of the air flow 70 as it leaves the exit duct. The louvers direct the air flow 70 inward (vehicle-wise) along the inboard side of the wheel well 50, between it and the steer wheel 52 and tire assembly.

-The highly engineered chassis fairing 72 that has a highly engineered chassis fairing 74 designed into it. The inboard surface of the chassis fairing vent 74 extends inward towards the centre of the motor vehicle 110. This allows the chassis fairing vent 74 to act like a scoop and to extract the air flow 70 of both the heat exchanger device 10 and the primary heat exchanger device 80 that has passed through the underhood area, as it flows along the inboard side of the wheel well 50. The air collected by the chassis fairing vent's 74 scoop then passes through the chassis fairing vent 74 and onto the exterior surface of the chassis fairing, where it rejoins the air flow 70 along the exterior of the motor vehicle 110.

The advantages of the heat exchanger device 10 and the motor vehicle 110 which comprises the heat exchanger device 10 are increased aerodynamic efficiency and the subsequent improvement in fuel economy and operating costs. Additional improvements include reduced wind noise and improved soiling.

List of reference signs heat exchanger device 12 fan 14 fan shroud heat exchanger bank air inlet element 32 inlet duct 34 inlet opening air guiding device 42 guiding element wheel well 52 wheel 54 air inlet 56 front portion 58 inner surface air flow 72 chassis fairing 74 chassis fairing vent primary heat exchanger device 82 grille 84 hood 88 separative element cross direction longitudinal direction motorvehicle 112 frontaxle

Claims

Claims A heat exchanger device (10) for a motor vehicle (110), the heat exchanger device (10) comprising: -at least one air inlet element (30) capable of directing an air flow (70) to at least one heat exchanger bank (20) of the heat exchanger device (10), which is arranged in front of a wheel well (50) of a wheel (52) according to the longitudinal direction (100) of the motor vehicle (110); and -an air guiding device (40) capable of directing the air flow (70) passing the heat exchanger device (10) around the wheel (52), characterized by -at least one air inlet (54) in a front portion (56) of the wheel well (50), the air inlet (54) being capable of directing the air flow (70) into the wheel well (50), and -at least one guiding element (42) of the air guiding device (40), the guiding element (42) being arranged at the air inlet (54) and the guiding element (42) being capable of guiding the air flow (70) along an inner surface (58) of the wheel (52) in the wheel well (50).
2. The heat exchanger device (10) according to claim 1, characterized in that, the heat exchanger device (10) is arranged beside a primary heat exchanger device (80) of the motor vehicle (110) according to the cross direction (90) of the motor vehicle (110) wherein the primary heat exchanger device (80) is arranged adjacent to a grille (82) of the motor vehicle (110) according to the longitudinal direction (100) of the motor vehicle (100).
3. The heat exchanger device (10) according to claim 1 or 2, characterized in that, the heat exchanger device (10) comprises at least one fan (12) which is configured to convey ambient air towards the at least one heat exchanger bank (20).
4. The heat exchanger device (10) according to any one of the preceding claims, characterized in that, the air inlet element (30) comprises at least one inlet duct (32) with a forward-facing inlet opening (34) according to the longitudinal direction (100) of the motor vehicle (110), the inlet opening (34) being capable of directing ambient air through the heat exchanger device (10).
5. The heat exchanger device (10) according to any one of the preceding claims, characterized in that, the guiding element (42) is designed as a louver.
6. The heat exchanger device (10) according to any one of claims 2 to 5, characterized in that, the primary heat exchanger device (80) and the heat exchanger device (10) are separated from each other by means of at least one separative element (88).
7. The heat exchanger device (10) according to any one of claims 2 to 6, characterized in that, the primary heat exchanger device (80) comprises at least one primary heat exchanger bank and at least one primary fan which is configured to convey ambient air towards the primary heat exchanger (80).
8. A motor vehicle (110) comprising a heat exchanger device (10) according to any one of the preceding claims.