FR2854119A1 - Aerodynamic configuration for terrestrial vehicle, extends from bumper face bar to front part that extends from front contact point, which is at level of radiators air outlet and upstream of air extracting slit and wheel cavities - Google Patents

Abstract

The configuration extends from a bumper face bar to a front part (43) of a base of a body panel in front of a passenger compartment. The front part extends from a front contact point of the vehicle. The point is very close to ground (15) at a level of an air outlet of a radiator and in upstream of a slit (13) for extracting air from internal circulation for a central part, and in upstream of wheel cavities.

Description

AUTOMOTIVE WITH VENTURI-CONTROLLED COOLING

  A) DO7M4INE OF THE I.NVENTION The present invention relates to the optimization of the cooling of automobile radiators and of any land vehicle in general. It also relates to the 5. control of the pressure prevailing in the front wheel arches.

  B) TECHNICAL STATE L4 The majority of current land vehicles and especially motor vehicles, use radiators placed at the front. This has the disadvantage of being expensive in terms of lift and drag of the vehicle.

  In addition, the design of the front wheel arches is made in such a way that pressure rises in these regions are observed, which results in a significant lift and induced drag.

  The object of the invention is to overcome these drawbacks.

  The object of the present invention is to define an optimal arrangement of the lower front of the vehicle making it possible to promote the cooling of the radiators and the brakes while overall reducing the lift and the drag of the vehicle.

  C) CONTENT OF THE FIGURES FIG. 1 represents the sectional view in conventional elevation FIG. 2 represents the sectional view in elevation equipped with a conventional screen under engine FIG. 3 represents the sectional view in elevation configured according to the invention FIG. 4 represents the sectional elevation view configured according to a variant of the invention.

  FIG. 5 represents the sectional elevation view configured according to another variant of the invention.

  along the center line of a vehicle along the center line of a vehicle along the center line of a vehicle along the center line of a vehicle along the center line of a vehicle FIG. 6 represents the side view of the wheel arch of a conventional vehicle FIG. 7 represents the sectional view in elevation of the wheel arch of a conventional vehicle FIG. 8 represents the section view in elevation of the wheel arch of a vehicle configured according to the invention FIG. 9 represents the sectional view in elevation of the wheel arch of a vehicle configured according to a variant of the invention FIG. 10 represents the view from below of the wheel arch of a vehicle configured according to the invention FIG. 11 represents the side view of the wheel arch of a vehicle configured 5. according to the invention FIG. 12 represents the sectional view of a variant of the front shoe configured according to the invention FIG. 13 represents the sectional view of another variant of the front shoe configured s according to the invention

  C) DESCRIPTION OF THE ELEMENTS OF THE FIGURES

  1) Upper cooling air inlet 2) Lower cooling air inlet 3) Leading edge and shaping of the lower part of conventional bodywork in the vehicle axis 4) radiator 5) engine 6) floor 7 ) rear apron of the engine, ie front apron of the passenger compartment, delimit the start of the passenger compartment 8) depression under the front part of the bodywork 9) shape of the envelope of the pressure field under the bodywork in front of the vehicle (the areas in depression are directed downwards) 10) on pressure in the air outlet zone 13 11) upstream end of the pressure casing 9 shown 12) downstream end of the pressure casing 9 shown 25 13) outlet area air 14) Fairing under a conventional engine, it is noted that the air outlet 13 is pushed very far back.

  15) Trailing edge of lower part 43 of bodywork according to the invention 16) Spoiler of trailing edge of lower part 43 of bodywork according to invention 30) Fairing under engine according to invention 18) Leading edge of the under-engine fairing according to the invention 19) Flow separator according to the invention.

  20) Flow separator according to the invention.

  21) Trailing edge of the wheel cavity seen from the side 35 22) Leading edge of the wheel cavity seen from the side 23) Trailing edge of the wheel cavity seen in section, between the wheel and the chassis.

  24) Leading edge of the wheel cavity seen in section, between the wheel and the chassis 25) Leading edge of the lower part of conventional bodywork in the wheel cavity axis 26) Leading edge of the part lower body according to the invention, seen from below 27) Classic limit of the wheel cavity, seen from below 28) Upstream flow separator wheel cavity according to the invention.

  29) Leading edge of the rear part of the wheel cavity according to the invention, seen from the side 30) Vehicle suspension elements 31) Vehicle suspension or transmission elements 32) Wheel 5. 33) Wheel arch 34) Edge for attacking the rear part of the wheel cavity according to the invention, zone between wheel and chassis 35) Fairing under suspension 36) Outer edge of lateral protection shoe and wheel fairing 10 37) Inner edge of lateral protection shoe and wheel fairing 38) Internal trailing edge of protective side shoe and wheel fairing 39) Trailing edge of the front part of the wheel cavity between wheel and chassis according to the invention 40) Trailing edge of the separator flow in the area of the wheel cavity between the wheel and chassis according to the invention 41) Lower leading edge of protective side shoe and wheel fairing 42) Leading edge halfway up of protective side shoe and wheel fairing 43) Leading edge e t shaping of the lower body part according to the invention in the vehicle axis.

  44) Variant of leading edge and shaping of the lower body part according to the invention in the vehicle axis 45) Variant of leading edge and shaping of the lower body part according to the invention in vehicle axis 46) Leading edge and shaping of the lower body part according to the invention in the area of the wheel cavity between wheel and chassis according to the invention 47) Variant of leading edge and shaping of the lower bodywork according to the invention in the area of the wheel cavity between wheel and chassis according to the invention 48) Engine compartment 30. 49) Lower model of the shoe directing the air towards the ground at the edge leakage 21 fig. 7 50) Inner channel of the shoe catching the air at the leading edge 42 and directing the air towards the ground at the trailing edge 21 fig. 8 51) Optional flow separator forming the lower part of the shoe of figure 8 52) Allure of the air flow under the shoe in configuration fig. 7 35 53) Pattern of air flow under the shoe in configuration fig. 8 54) trailing edge flap 21 located as close to the wheel as possible and as low as possible, note this flap may be made of deformable materials, which allows it to be placed at an even lower ground clearance 55) preferential interior extension and outer side shoe for protection and wheel fairing D) PRINCIPLE OF CLASSIC INTERNAL TRAFFIC Under a conventional vehicle the underside 3 figure l and 2 as well as 26 fig. 6 of the vehicle is very poorly drawn and is generally decked out with a spoiler intended to prevent too much air from rushing under the vehicle.

  If we measure the pressure field 9 without spoiler in this area we observe that in fact there is there a considerable depression potential badly located from which we take no advantage.

  Vehicles without engine fairing have a large outlet for engine cooling air. This zone having a very low flow rate and a large roughness generates lift (pressure 10) and aerodynamic drag. 10 Vehicles fitted with under engine fairing 14 have a more reasonable air outlet 13 in Figure 2 generally located near the rear engine bulkhead 7.

  once again, these outputs are relatively large and ineffective in terms of dynamic pumping of the engine compartment.

  The conventional internal circulation is motorized at high speed by the stop pressure which applies to the air inlets l & 2, at low speed a fan assists the sweeping.

  E) PRINCIPLE OF THE INVENTION: CONTROLLED INTERNAL CIRCULATION

BY VENTURI EFFECT

  The internal circulation according to the invention is motorized at high speed by the pressure difference between the stop pressure which applies to the air inlets 1 & 2 and the powerful vacuum obtained by the venturi effect which is fitted to the right of the air outlet 13 naturally at low speed a fan assists the sweeping.

  BERNOULLI's theorem specifies that in a flow: Total pressure = static pressure + dynamic pressure. 25 Applied to a Laval nozzle (in other words to a venturi) the BERNOULLI theorem allows us to demonstrate that it is possible to obtain a static depression at the considerable neck insofar as the air flow has undergone a significant increase in speed compared to the venturi inlet area.

  If we consider the vehicle to be developed, the ground, which passes under the vehicle can be compared to the plane of symmetry of a two-dimensional Laval nozzle whose walls and its symmetrical image under the ground are the walls.

  So if one wishes to optimize the design of the front of the vehicle according to the invention, the walls 43 fig. 3, 44 fig. 4 or 45 fig. 5 are designed so that they greatly accelerate the flow picked up at the front of the vehicle, the convergence of the shapes towards the neck of the venturi organized under the vehicle makes it possible to obtain the maximum speed of the flow, (and therefore static depression at the maximum wall) to the right of the air outlet 13 which is the lowest point of the lower part of the vehicle.

  FIG. 3 shows a progressive convergent 43 having an angle of 15 to 30 degrees 5. relative to the ground. This convergent can possibly end in a flap 16 beyond its natural trailing edge 15.

  Preferably, the leading edge of the following engine fairing is rounded along 18 in order to guide the air and ensure good bonding of the flow.

  FIG. 4 shows a convergent type of blower 44 having a profile with double curvature with respect to the ground.

  This convergent can possibly be supplemented by a flow separator 19 whose role is to increase the efficiency of the speed setting and the improvement of the downforce.

  FIG. 5 shows a convergent of the progressive type or of the convergent type of blower 45 fitted with one or two flow separators.

  Figure 6 shows the rating of a classic car seen in elevation.

  The conventional pressure fields 9 that we observed in FIG. 1 in the center line of the vehicle are found in this area also. The conventional wheel cavities are the seat of a significant pressure which tends to degrade the lift and the drag of the vehicle.

  The same is true in FIG. 7, where a cross-section is shown between the wheel and the chassis of the vehicle in the wheel arch.

  FIG. 8 is the direct transposition of the principles of the invention, as described for pumping the internal circulation in FIG. 3, applied to the depression of the wheel cavity 33.

  Such a device ensures better vehicle stability, it reduces its drag as well as its lift while ensuring the natural cooling of the front brakes by suction of cool air through the rims openings.

  The fairing under suspension 35, with its ski shape, at its leading edge, makes it possible to stabilize the jet coming from the trailing edge 39 and to lead it to the rounded leading edge 34 of the bottom cavity apron of wheel 33.

  FIG. 9 is a variant corresponding to the direct transposition of the principles of the invention, as described for pumping the internal circulation in FIG. 4, applied to the depression of the wheel cavity 33.

  The flow separator 28 plays a role similar to the separator 19 or 20 described in FIGS. 4 and FIGS. 5.

  Figure 9 gives an overview of the molten wheel cavity area from below.

  It is observed that a shoe is placed upstream of the wheel in order to fair it.

  The air collected between the leading edge of the right shoe and the left shoe is therefore used, on the sides to depressurize the wheel cavities and in the center to depressurize the engine compartment 48.

  Compared to the classic wheel cavity solution having a shape as described by the line 27 in figure 10, we recommend the fairing in the shape 35 which stabilizes the flow and limits its penetration into the upper part of the cavity wheel.

  5. Figure 1 1 shows a side view of the vehicle. We see the leading edge 42 of the hoof it can be straight or curved as drawn it is connected to the lower part 41 of the leading edge of the hoof.

  The trailing edge of the shoe 21 is preferably completed by a flap 54 which makes it possible to hide the wheel as close as possible to it.

  Figure 12 shows a sectional view of a preferred shoe configuration.

  In the background, there is the edge of the shoe 36. and in the foreground the curved shape 49 in the form of a question mark, this makes it possible to capture the air arriving horizontally and to direct it towards the ground, as shown in the illustration. flow 52; This allows to hide the wheel as much as possible and limit its drag.

  Figure 13 shows a sectional view of a preferred shoe configuration.

  We can see in the background the shoe edge 36. and in the foreground the channel 50 whose purpose is to capture the air arriving horizontally and to direct towards the ground, as shown in the flow illustration 53; This allows to hide the wheel as much as possible and limit its drag. The optional separator 51 makes it possible to channel the flow.

  Note: 1. all that has been described above and as far as possible, should preferably be followed by a fairing, as smooth as possible, in the extension of the fairing 17, over the entire length and width of the vehicle 2. What has been described above applies to any vehicle in particular in the event of front cooling and engine not necessarily placed at the front of the vehicle.

  3. What has been described above applies to any vehicle and in particular in the absence of front cooling insofar as the device makes it possible to generate a vacuum which can be applied to the front wheel arches.

  4. The trailing edge 39 of the wheel arch can preferably be extended by a flap in the style of the flap 16 which equips the trailing edge of the fairing 43 (FIG. 3).

  5. The wheel cavity flap as described above can be directed towards the ground, as in FIG. 3 or preferably horizontal.

  6. Preferably, the shoes descend as low as possible in the authorized clearance clearance and they are placed in the axis of the wheels to fair them as closely as possible. That is to say that preferably they have substantially the width of the wheel not turned.

  7. An interesting form of the shoe seen from below (fig 10) is that the outer wall 36 resembles the inner wall 37 (as drawn in fig 10), which resembles a conventional NACA air intake and can allow to favor the functioning of the design presented in figure 12 by balancing it.

  8. in the extension of the trailing edge 21 of the shoe as described by Figures Il 12 & 13, preferably a flap 54 vertical or slightly curved backwards or forwards in and preferably bordered by complementary walls 55 can be placed just and as close as possible upstream of the wheel, and possibly can penetrate the prohibited ground clearance zone if it is made with a flexible synthetic material 5- a * Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, and extending from the bumper to the front apron of the passenger compartment, preferably over the entire width of the vehicle, characterized in that the front part 43, 44, 45, 46, 47 extending from the front end of the vehicle under it has its furthest point near the ground 15 at the radiator air outlet 4, just downstream from it.

  * Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, and extending from the bumper to the front apron of the passenger compartment, preferably over the entire width of the vehicle, characterized in that the front part 43, 44, 45, 46, 47 being understood from the front point of the vehicle under it at its point closest to the ground just upstream 39 of the front part of the front wheel arch 33.

  * Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to claims 1 & 2 characterized by, the presence of an engine compartment fairing 17 preferably leaving only a very small space 13 allowing the air from the internal circulation outlet as close as possible to the trailing edge 15 of the fairing 43.44. or 45.

  * Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to the preceding descriptions, characterized by the curved shape 18 of the leading edge of the fairing 17.

  * Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to the preceding descriptions, characterized by the presence of shoes placed in front of the wheels 32 delimited by the shapes 41, 36 21, 37 view from below.

  * Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to the preceding descriptions, characterized by the presence of a radiated leading edge 34, 29 of the wheel arch 33.

  * Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to the preceding descriptions characterized by, the presence of a fairing 35 of the 40-wheel cavity 33, preferably the leading edge is tilted upward, as shown in Figure 9.

  * Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to the preceding descriptions, characterized by the presence of flow separators 19.20 & 28.

  ò Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to the preceding descriptions characterized by, the presence of a cavity 49 fig 12 in the form of a question mark substantially, seen in elevation. This cavity is preferably delimited laterally by the walls 37 & 36.

  Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to the preceding descriptions, characterized by the presence of a cavity 50 fig. 13 open in 10 the shape of the leading edge of the shoe above the point 41 this cavity preferably closed horizontally on its lower front part by a separator 51 ends with a trailing edge 21 oriented downwards Aerodynamic configuration optimized according to the invention, relating to the front part of the underbody of a land vehicle, according to the preceding descriptions, characterized in that the leakage 21 is extended by a flap 54 vertical or slightly curved towards the rear or towards the front and preferably bordered by complementary walls 55. this flap 54 can be placed just and as close as possible upstream of the wheel, and possibly can penetrate the area of ground clearance prohibited if it is made with a flexible material

Claims (8)

  1. Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, and extending from the bumper to the front apron of the passenger compartment, preferably over the entire width of the vehicle, characterized in that the front part 43, 44, 45, 46, 47 extending from the front point of the vehicle under it at its point closest to the ground 15 at level 25 of the radiator air outlet 4, just downstream thereof.   2. Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, and extending from the bumper to the front apron of the passenger compartment, preferably over the entire width of the vehicle, characterized in that the front part 43, 44, 45, 46, 47 being understood from 30 the front point of the vehicle under it at its point closest to the ground just upstream 39 of the front part of the front wheel arch 33.   3. Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to claims 1 & 2 characterized by, the presence of an engine compartment fairing 17 preferably leaving only a very small space 13 allowing the air from the internal circulation outlet as close as possible to the trailing edge 15 of the fairing 43.44. or 45. I   4. Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to claims 1,2 & 3 characterized by, the curved shape. 18 from the leading edge of the fairing 17.   5. Optimized aerodynamic configuration according to the invention, concerning the front part 5. of the underbody of a land vehicle, according to claims 1.2.3 & 4 characterized by the presence of shoes placed in front of the wheels 32 delimited by the shapes 41 , 36 21, 37 view from below.   6. Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to claims 1.2 3. 4. & 5 10 characterized by the presence of a radiated leading edge 34, 29 of the wheel arch 33.   7. Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to claims 1.2 3. 4. 5 & 6 characterized by, the presence of a fairing 35 of the wheel cavity 33 including preferably the leading edge is inclined upwards, as shown in FIG. 9.   8. Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to claims 1.2 3. 4. 5.6 & 7 characterized by the presence of flow separators 19.20 & 28.   9. Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to claims 1.2 3. 4. 5. 20 6. 7 & 8 characterized by the presence of a cavity 49 fig 12 substantially shaped like a question mark, seen in elevation. This cavity is preferably delimited laterally by the walls 37 & 36.   10. Optimized aerodynamic configuration according to the invention, concerning the front part of the underbody of a land vehicle, according to claims 1.2 3. 4. 5. 25 6. 7. 8 & 9 characterized by, the presence of a cavity 50 fig. 13 open in the shape 42 of the leading edge of the shoe above the point 41 this cavity preferably closed horizontally on its lower front part by a separator 51 ends with a trailing edge 21 oriented downwards 11. Optimized aerodynamic configuration according to the invention, relating to the front part of the underbody of a land vehicle, according to claims 1.2 3. 4. 5.   6. 7. 8.9 & 10 characterized in that the leakage 21 is extended by a vertical flap 54 or slightly curved towards the rear or towards the front and preferably bordered by complementary walls 55. this flap 54 can be placed just and at most ready upstream of the wheel, and possibly can penetrate the area 35 of ground clearance prohibited if it is made with a flexible material