FR3062627B1 - DEVICE FOR REDUCING THE TRAINING OF A MOTOR VEHICLE BY DRAINING SURPRISING AIR TO A REAR WHEEL PASSAGE OF THE VEHICLE. - Google Patents

Abstract

The invention relates to a device for reducing the drag of an automobile vehicle (1) and a motor vehicle equipped with a body provided with such a device. The device comprises at least a first conduit (8) for supplying a first air flow (Fa1) flowing from upstream to downstream in the direction of flow of air (Sa1) along the vehicle (1) moving forward (Sav). The first duct (8) extends from at least one upstream air retention zone (3a) (a2) which comprises the vehicle body (1) towards the inside of a downstream rear wheel arch (4). of the vehicle (1).

Description

Device for reducing the drag of a motor vehicle, by draining excess pressure air towards a rear wheel arch of the vehicle.

The present invention relates to the field of motor vehicles and in particular the arrangements for arranging the body of a motor vehicle to promote its aerodynamics. The invention relates more specifically to a drag reduction device of a motor vehicle promoting an air flow along the vehicle body.

The body of a motor vehicle gives it essentially its aerodynamics and aesthetic style.

Regarding the aerodynamics of the vehicle, the body is particularly shaped to promote the flow of air along the vehicle longitudinally from front to back. It is essentially sought to provide the vehicle with a high performance stability when progressing, especially forward indicative fast speeds greater than 90 km / h (ninety kilometers per hour). It is also sought to reduce its drag to promote its progression and limit its consumption of motive power, including its consumption of fuel and / or electricity.

To promote the flow of air along the bodywork, the bodywork can ideally have a regular line. Such a regular line allows in particular to avoid the localized formation of troughs and / or transverse projections along the bodywork. As the vehicle progresses, such depressions and / or projections promote the formation of air pockets, or in other words air retention zones. Such air retention zones, in particular directed towards the front of the vehicle, obstruct the flow of air towards the rear of the vehicle by providing local areas of overpressurized air along the bodywork. .

However, a regular line of the bodywork implies a lack of shapes that can be formed along the bodywork, for example to promote the stability and / or grounding of the vehicle in progression. Such shapes include for example side flaps, or bulges and / or cavities having a transverse extension relative to the longitudinal axis of progression of the vehicle.

In addition, the body of a motor vehicle is also arranged to confer an aesthetic style to which the customer is sensitive in the act of purchasing a vehicle. An attractive aesthetic style for the customer often creates shapes along the bodywork which generate overpressure air retention zones when the vehicle is moving forward.

Such air retention zones in overpressure are in particular configured in recesses, or cavities open frontally to the flow of air flowing along the bodywork. For example, transverse enlargements of the rear fenders of the vehicle give it a particular aesthetic style, but are configured in bulges that provide such areas of air retention.

Regarding the reduction of the drag of the vehicle, it is known to provide in the body of the air ducts from the front to the rear of the vehicle. As the vehicle progresses, air flows through the ducts to evacuate to the rear of the vehicle to reduce drag.

In this regard, reference may be made to FR3012787 (PEUGEOT CITROEN AUTOMOBILES SA). This document describes a device for reducing the drag of a vehicle by creating an air flow between an air overpressure zone generated during the progression of the vehicle and a vacuum zone created in the wake of the vehicle. More specifically, according to the direction of flow of the air flow, a duct conveys the flow of air from a rear wheel well to the rear of the vehicle.

On the basis of the finding that has just been made and which relates to the approach taken, the invention relates to a device for reducing the drag of a motor vehicle.

The object of the invention is to manage, vis-à-vis the aerodynamics of the vehicle, the problems posed by an attractive architecture for customers of the body of the vehicle.

It is more specifically targeted by the invention to allow a development of the body of the vehicle that can appeal to customers while limiting its impact on an increase in the drag of the vehicle.

It is even more specifically targeted by the invention to allow a development of the vehicle body that can promote the stability and / or grounding of the vehicle in progression, while avoiding the formation of air overpressure zone along the lines. side bodywork elements of the vehicle.

It is already specified some geometric concepts typically used in the automotive field and may if necessary be useful to better understand the invention.

The notion of longitudinal extension of the vehicle and / or elements or sets of bodywork elements which it is provided is typically considered between the front and the rear of the vehicle. The fore and aft concepts are relative concepts conventionally identified according to the station of the driver on board the vehicle, which faces the direction of advancement towards the front of the vehicle.

The direction of air flow is considered from the front to the rear of the vehicle, the vehicle progressing substantially forward. Thus, the upstream and downstream notions are relative notions considered according to the direction of flow of air as just specified.

The transversal and vertical notions are valued perpendicularly to each other and to the notion of longitudinal. The vehicle extends transversely between its longitudinally extended lateral sides at the right and / or left sides of the vehicle relative to the driver's station. The vehicle extends vertically or in elevation perpendicular to its taxiing plane. The notions low and high and / or the notions base and vertex, are relative notions considered with respect to the concept of verticality with respect to the rolling plan of the vehicle extending to the base of the vehicle.

The aims of the present invention are achieved by applying the following provisions, considered alone or in combination when they are compatible with each other.

The device of the invention comprises at least a first duct for supplying a first flow of air flowing from upstream to downstream in the direction of flow of the air along the vehicle traveling towards the before. Such a first duct may be attached to and / or be integrated with at least one bodywork element covering the lateral sides of the vehicle.

The first conduit extends in particular between at least one upstream outlet and at least one downstream outlet that it comprises. The notions upstream and downstream are understood as relative notions considered according to the direction of flow of the air along the vehicle progressing forward and / or following the direction of flow of the first air flow to the air. inside the first conduit. The first conduit is configured to route the first flow of air through it from its outlet upstream to its outlet downstream which are open to the outside of the vehicle.

According to the invention, the first conduit extends from at least one upstream air retention zone that includes the vehicle body to the interior of a rear wheel well downstream of the vehicle.

In other words, the device of the invention comprises at least a first duct for supplying the first air flow from at least one overpressure air retention zone formed by the vehicle body to a vacuum zone of air formed by the recess of the rear wheel arch open towards the outside of the vehicle. The air likely to be held in overpressure in the air retention zone during the progression of the vehicle forward is thus able to be admitted inside the outlet upstream of the first conduit. The first flow of air is formed by driving the air retained in overpressure in the air retention zone towards the interior of the first duct, under the effect of the progression of the vehicle forward. The first flow of air then circulates inside the first conduit and is discharged from the first conduit to its outlet downstream to the inside of the wheel well for its depression. It is thus avoided a possible excess air pressure inside at least one air retention zone that includes the vehicle body upstream of the rear wheel well.

The first conduit is in particular configured on the vehicle body being able to drain the inside of the rear wheel well overpressurized air from at least one said air retention zone. The pressurized air that can be housed in the air retention zone is conveyed by the first duct to the rear wheel well for its depression and thus avoid an air overpressure in the air retention zone.

The drag of the vehicle is reduced by capturing the air retained in the one or more air retention zones and by adding the first air flow through the first duct to the rear wheel well. Random dispersion along the vehicle body of the air that can be retained in the air retention zone is thus avoided. Such random dispersion is disruptive of a laminar flow of air along the vehicle backward as it progresses forward, especially at high speeds.

The air retention zone is frontally open towards the front of the vehicle by obstructing a flow of air along and towards the rear of the vehicle as it progresses forward. Such an air retention zone is for example typically delimited by at least one pocket, a cavity and / or a hollow more or less extended vertically and / or transversely formed in the bodywork.

Thus, a freedom of shaping of the body is provided by avoiding increasing the drag of the vehicle, to give the vehicle a particular aesthetic style that may be attractive to the customers of motor vehicles and / or to stabilize the vehicle when of his progress.

According to one embodiment, at least one downstream outlet of the first duct on the wheel well is configured as a guide ramp for the first air flow at the outlet of the first duct according to a flow of the first air flow along the outlet of the duct. wheel arch oriented laterally towards the outside of the vehicle.

It can thus be formed a curtain of air along the outlet of the wheel well providing an optimized laminar flow of air along the wheel well. Such an air curtain reduces the turbulence usually generated by the air flowing in the wheel arches. The air coming from at least one air retention zone and drained by the first duct is thus used to form the air curtain. The drag of the vehicle is further reduced and the aerodynamics of the vehicle is improved. The noise nuisance usually generated by the turbulence is also reduced and passenger comfort is improved.

At least one upstream outlet of at least one first duct is for example open on at least one air retention zone formed by a bulge of a rear wing of the vehicle and / or formed by a form of style of the bodywork. extending at the edge of at least one side door of the vehicle.

In other words, at least one first duct captures air from at least one air retention zone formed in hollow by a bulge of the vehicle body covering a rear wing of the vehicle and / or by a shape of the vehicle. bodywork extending for example along the edge of at least one side door of the vehicle, including a rear door.

According to one embodiment, at least one upstream outlet of at least one first conduit is provided at the base of at least one air retention zone. The totality of the air contained in the air retention zone may be entrained towards the inside of the first duct, the extension of which may then be limited from the air retention zone to the rear wheel well.

According to one embodiment, at least one upstream outlet of at least one first conduit is open towards the bottom of the vehicle. In other words, the air contained in the air retention zone is in this case taken by the first duct from a direction towards the bottom of the vehicle.

Preferably, the device comprises at least a second conduit which extends towards the rear face of the vehicle from at least one upstream outlet of the second conduit on the rear wheel well.

The rear face of the vehicle is typically its side oriented transversely to the vehicle and extending between its side flanks at the rear of the vehicle. The formation of the air curtain along the outlet of the wheel well is supported, the first air flow guided by the ramp at the outlet of the first conduit then being driven to the upstream outlet of the second conduit.

More particularly, the first duct and the second duct together form a ventilation device generating a curtain of air along the outlet of the wheel well oriented laterally towards the outside of the vehicle.

In other words, the first duct and the second duct are cooperating with each other by forming a drive member of a third air flow forming the air curtain along the outlet of the rear wheel well, from the downstream outlet of the duct. first conduit to the upstream outlet of the second conduit.

According to one embodiment, the first conduit is capable of having a plurality of upstream branches, whose upstream outlets are open on several air retention zones assigned to them. The upstream branches converge to a downstream portion of the first conduit which opens onto the rear wheel well.

The present invention also relates to a motor vehicle equipped with a body provided with a device according to the invention.

More particularly, a vehicle according to the invention is dressed with a body providing at least one said air retention zone formed upstream of a rear wheel well in the direction of flow of air along the the bodywork as the vehicle progresses forward. The body is equipped with at least one said first duct, an upstream opening is open on at least one said air retention zone and a downstream outlet is open on the rear wheel well.

In other words, the body of the vehicle is provided with at least one said first air supply duct retained overpressure in at least one said air retention zone to a rear wheel well of the vehicle. At least one said first conduit is in particular formed along each of the lateral sides of the vehicle dressed by the bodywork.

Preferably, the vehicle body is also equipped with at least one said second conduit whose upstream outlet is open on the rear wheel well and whose downstream outlet is open towards the rear of the vehicle.

The second conduit carries a second air flow from the rear wheel well to the rear of the vehicle. The upstream outlet of the second conduit is in particular disposed substantially vis-à-vis the downstream outlet of the first conduit. The first conduit and the second conduit cooperate with each other to promote the generation of the air curtain. The air from which the air curtain is drawn is the air drained by the first duct from at least one said air retention zone and sent through the first duct to the rear wheel well.

The bodywork for example comprises bulges of the rear fenders of the vehicle and / or a form of style extending along a side door of the vehicle, including each of the rear side doors of the vehicle. Said form of style is in particular transversely protruding towards the outside of the vehicle. At least one said air retention zone is formed by at least one of said bulge and / or a said shape of style.

Embodiments of the present invention will be described in connection with the figures of the accompanying drawing in which: -) Figure 1 is a rear perspective illustration of a motor vehicle, the body is equipped with a device reduction of its drag according to an exemplary embodiment according to the invention. -) Figure 2 is a top view of a motor vehicle whose body is equipped with a drag reduction device according to an exemplary embodiment according to the invention. - Figure 3 is an illustration in perspective before an embodiment according to the invention of a drag reduction device of a motor vehicle equipping his body.

The figures and their description set forth a detailed description of the invention and particular methods of its implementation. The figures and their detailed description may if necessary be used to better define the invention, particularly in relation to the general description which has just been made.

In Figures 1 to 3, the extension directions of a vehicle 1 automobile are typically identified in an orthonormal reference DL, DT, DV. The orthonormal mark DL, DT, DV is defined by a longitudinal direction DL extending between the front 1a and the rear 1b of the vehicle 1, by a transverse direction DT extending between the sides or in other words between the lateral flanks 2 of the vehicle 1, and a vertical direction DV extending in elevation upwards from the PR plane of the vehicle 1.

It is also typically identified a main direction of forward progression of the vehicle 1. As the vehicle 1 progresses forward Sav, a flow of air Fa scans the entire body of the vehicle 1 from the front 1a to the rear 1b, in a direction of air flow Sa1 oriented longitudinally. Subsequently, the concepts upstream and downstream are identified according to said air flow direction Sa1.

In Figures 1 and 2, the body of the vehicle 1 comprises recesses 3 formed upstream of each of the rear wheel passages 4. In the illustrated example, such recesses 3 are formed by bulges 5 drawing a transverse extension of the rear wings 6 laterally towards the outside of the vehicle 1, and / or by a 5 'style shape bordering at least one side door 7 of the vehicle, including the rear.

Such bulges 5 and / or 5 'style shape are likely to appeal to customers and favor the act of purchase of the vehicle 1. However, it follows a transverse extension of the dug 3 from the side walls 2 of the vehicle 1. The recesses 3 then typically form retention zones 3a of air a2 under excess pressure when the vehicle progresses forward Sav. Such air pressures a2 upstream of the bulges 5 and / or 5 'style shapes increase the drag of the vehicle 1 and consequently increases its consumption of propulsive energy.

Such an increase in energy consumption is a discriminating factor affecting the seduction of the customers for the purchase of a vehicle 1. It is therefore useful to reduce the drag of the vehicle 1, the increase of which is notably caused by the formation of the vehicles. retention zones 3a air a2 overpressure along the vehicle 1 as it progresses forward Sav.

More particularly, it is useful to propose a solution to reconcile a vehicle aesthetic style 1 delimiting retention zones 3a air a2 overpressure and a reduction of the drag of the vehicle 1 which tends to be increased by the presence of such areas 3a retention air a2 overpressure.

In this context in Figures 1 to 3, the vehicle body 1 is provided with a vehicle drag reduction device 1. The body of the vehicle 1 is substantially symmetrical on either side of a transverse longitudinal axis. median of the vehicle, the following provisions are applied in particular for each of the rear side zones of the vehicle 1.

The device comprises at least a first duct 8 configured to drain air a2 at excess pressure held in the retention zones 3a of air a2, to a rear wheel well 4 of the vehicle 1. More particularly, at least a first duct 8 comprises at least one upstream outlet 8a open on at least one retention zone 3a of air a2 and at least one open outlet 8b open on the rear wheel passage 4.

The first duct 8 is configured for the conveyance therethrough towards the rear wheel arch 4 of a first air flow Fa1 whose air a2 under excess pressure is taken by the first duct 8 from the retention zone of the duct. air 3a. Thus the a2 air at excess pressure retained in the retention zones 3a of air when the vehicle 1 progresses forward Sav, is conveyed by the first conduit 8 upstream downstream to an air depression zone formed by the wheel arch 4 rear.

The drag of the vehicle 1 is thus reduced and an aesthetic style of the body of the vehicle 1 providing retention zones 3a of air a2 overpressure upstream of the wheel arches 4 rear can be sought to seduce the customer in its act d purchase of the vehicle 1.

In FIG. 3, the upstream outlet 8a of the first duct 8 is oriented towards the bottom of the vehicle 1. More particularly, referring to FIG. 1, the bulge 5 and the 5 'style shape converge towards the base of the retention 3a of air a2 formed by the hollow 3. The first conduit 8 is formed at the base of the retention zone 3a of air a2 which allows in particular to reduce its extension between the retention zone 3a air a2 to the rear wheel arch 4, its upstream outlet 8a preferably being oriented towards the bottom of the vehicle 1.

In the specific examples illustrated in FIGS. 1 to 3, the device also comprises at least one second duct 9 which extends from the rear wheel well 4 to the rear 1b of the vehicle 1. The second duct 9 is configured to convey a second air flow Fa2 from the rear wheel arch 4 to the rear 1b of the vehicle 1. More particularly, at least one second duct 9 comprises at least one upstream opening 9a open on the rear wheel arch 4 to take off the air that it contains and at least one open outlet 9b open on the rear 1b of the vehicle 1.

The first duct 8 and the second duct 9 cooperate with each other to form a ventilation device 8, 9 which generates a third air flow Fa 3 forming an air curtain Fa 3 along the outlet of the rear wheel arch 4 oriented laterally. to the outside of the vehicle 1. The downstream outflow 8b of the first duct 8 may advantageously be designed as a guide ramp for the first air flow Fa1 towards the upstream outlet 9a of the second duct 9. Thus, the air has admitted to the rear wheel arch 4 is driven towards the second duct 9, forming at least partly the air from which the air curtain Fa3 originates.

Claims (10)

1, -A device for reducing the drag of an automobile vehicle (1) comprising at least a first conduit (8) for supplying a first air flow (Fa1) flowing from upstream to downstream according to the direction of airflow (Sa1) along the forwardly moving vehicle (1) (Sav), characterized in that the first duct (8) extends from at least one retention zone (3a ) air (a2) upstream that comprises the vehicle body (1) inwardly of a rear wheel well (4) downstream of the vehicle (1). 2, - Device according to claim 1, characterized in that at least one downstream outlet (8b) of the first conduit (8) on the wheel well (4) is configured as a guide ramp of the first air flow ( Fa1) at the outlet of the first duct (8) according to a flow of the first air flow (Fa1) along the outlet of the wheel well (4) oriented laterally towards the outside of the vehicle (1). 3, - Device according to any one of claims 1 and 2, characterized in that at least one upstream outlet (8a) of at least one first conduit (8) is open on at least one retention zone (3a) air (a2) formed by a bulge (5) of a rear wing (6) of the vehicle (1). 4, - Device according to any one of claims 1 to 3, characterized in that at least one upstream outlet (8a) of at least one first conduit (8) is open on at least one retention zone (3a) air (a2) formed by a form of style (5 ') of the bodywork extending along the edge of at least one side door (7) of the vehicle (1). 5, - Device according to any one of claims 1 to 4, characterized in that at least one upstream outlet (8a) of at least one first conduit (8) is formed at the base of at least one zone of retention (3a) of air (a2). 6, - Device according to any one of claims 1 to 5, characterized in that at least one upstream outlet (8a) of at least one first conduit (8) is open towards the bottom of the vehicle (1). 7, - Device according to any one of claims 1 to 6, characterized in that the device comprises at least a second conduit (9) which extends to the rear face (1b) of the vehicle (1) since at least an upstream outlet (9a) of the second conduit (9) on the rear wheel arch (4). 8, - Device according to claim 7, characterized in that the first duct (8) and the second duct (9) together form a ventilation device generating an air curtain (Fa3) along the outlet of the wheel arch (4) oriented laterally towards the outside of the vehicle (1). 9, - Device according to any one of claims 1 to 8, characterized in that the first conduit (8) comprises a plurality of upstream branches whose upstream outlets are open on several retention zones (3a) of air (a2 ) which are assigned to them and which converge to a downstream portion of the first conduit (8) which leads to the rear wheel well (4). 10, -Vehicle (1) automobile equipped with a body provided with a device according to any one of claims 1 to 9.