Claims:We claim:
1. An apparatus for improving aerodynamic drag to improve fuel consumption in vehicle (201), the apparatus comprising:
a fluid duct (204) provided in front overhanging area (202) of the vehicle (201) for directionalizing flow of exterior air towards rear (209) of front wheel (208), the fluid duct (204) comprising:
a fluid inlet (205) provided at front end of the fluid duct (204) for receiving the exterior air;
a fluid outlet (206) provided at rear end of the fluid duct (204) to exhaust the directionalized exterior air with high pressure towards the rear (209) of the front wheel (208) to reduce wake region for improving the aerodynamic drag.

2. The apparatus as claimed in claim 1, wherein the fluid inlet (205) is provided at front end of the vehicle (201) with a grill having plurality of openings.

3. The apparatus as claimed in claim 1, wherein the fluid outlet (206) is provided above the rear (208) of the front wheel (209) in front overhang area (202) of the vehicle (201) to reduce the wake region.

4. The apparatus as claimed in claim 1, wherein the fluid duct (204) has curved profile according to curvature of the front wheel, wherein the curved profile of the fluid duct (204) provides high pressure flow to the air.

5. The apparatus as claimed in claim 1, wherein the fluid inlet (205) has big cross section area than the fluid outlet (206).

6. The apparatus as claimed in claim 1, wherein the fluid outlet (206) releases the directionalized air flow directly towards the wake region with high pressure.

7. The apparatus as claimed in claim 1, wherein the apparatus provides a uniform air flow at side body near fender region of the vehicle (201).

8. The apparatus as claimed in claim 1, wherein the apparatus reduces pressure difference between front end and back end of the vehicle (201).

9. The apparatus as claimed in claim 1, wherein the apparatus increases air pressure at rear side of the vehicle (201) by directing smooth air flow toward rear side of the vehicle.
, Description:AN APPARATUS FOR REDUCING WAKE REGION OF WHEEL AND TO IMPROVE AERODYNAMICS OF VEHICLE
FIELD OF INVENTION:
[001] The present subject matter described herein, relates to aerodynamics of the vehicle, and, in particular, to an apparatus for reducing wake region/area of front wheel for improving aerodynamics of the vehicle. In more particularly, the present subject matter relates to a fluid duct provided in front overhang area/region of the vehicle to direct exterior air at rear of front wheel to reduce the wake region of the front wheel and improve the aerodynamics of the vehicle.
BACKGROUND AND PRIOR ART:
[002] A significant portion of the operational costs of a modern motor vehicle arises from the consumption of fuel. Motor vehicles with internal combustion engines typically burn fossil fuels, such as gasoline or diesel. The relative usage of fuel by a motor vehicle is known as fuel efficiency, and is also known as fuel economy. Increased fuel prices also have a significant detrimental impact on the economy, as they can deter travel; increase the cost of transportation or manufacture of goods, etc.
[003] Motor vehicles, such as automobiles, sports utility vehicles (SUVs), vans, and trucks, require a propulsive force in order to move the vehicle. This propulsive force must overcome the drag of the vehicle in order for the vehicle to move forward. Drag on a vehicle originates from a number of sources, including aerodynamic drag and tire drag (resulting from frictional forces caused by the tire-road interaction). Propulsive force is typically generated by engine, such as internal combustion engine, fuel cell, electrical engine, etc.
[004] Aerodynamic drag includes both frictional drag and pressure drag. Frictional drag derives from friction between the fluid (air) and the surfaces of the vehicle over which it is flowing. The velocity of the air moving over the surfaces of the vehicle is known as the free stream velocity. The free stream velocity is based on the speed of the vehicle and the prevailing wind. For example, if speed of a vehicle is 100 kmph and is heading directly into a 15 kmph headwind, the free stream velocity would be 115 kmph. The air moving over the surfaces of the vehicle, a boundary layer is typically formed along the surface of the vehicle, serving as a transition between air at zero velocity right at the surface and air at the free stream velocity at the edge of the boundary layer. The boundary layer may contain both laminar (smooth) flow and turbulent flow. Often, near the rear of a vehicle, the flow “separates”, meaning that the boundary layer separates from the surface, resulting in eddies and fully turbulent flow. The drag caused by the air in the boundary layer creates frictional drag.
[005] Pressure drag (also known as form drag) results from the difference in pressure between the front of the vehicle and the rear of the vehicle. Accordingly, it depends on the size and shape of the vehicle. When the airflow separates on the vehicle, lower pressures are created behind the vehicle than would exist in the absence of separation, resulting in increased pressure drag. This problem is exacerbated on less aerodynamic vehicles, such as SUV's and trucks, as their relatively blocky shape causes additional separation and thus additional pressure drag. The pressure behind a vehicle may drop low enough, particularly, when moving at high speeds, to create wake (vacuum-like conditions) behind the vehicle, resulting in very high pressure drag.
[006] Hence, Aerodynamic drag is one of the largest contributors to the total resistance that the vehicle has to overcome when moving. Further, a large part of fuel is expended in overcoming the aerodynamic drag and to move the vehicle in forward direction. Therefore, fuel efficiency of the vehicle depends on the aerodynamic drag of the vehicle.
[007] Fig. 1 illustrates flow of air at exterior of the vehicle. The air flow smoothly at surface 101 of the vehicle. The air flow is turbulent at the edge and at rear side 103 of the vehicle where the air flow separates from the smooth surface of the vehicle. Lower part or under body of the vehicle also contributes in the aerodynamic drag of the vehicle. Further, the four wheels 102 of the vehicle play an important role in the total aerodynamic drag of the vehicle. In the existing model, the front of a vehicle while moving creates a pushing force on the vehicle and also tends to divert the flow towards sides (Left or right), upwards, and downwards. Due to this there is wake area generated at the rear of front wheel. This low pressure region at the rear side of front wheel disturbs the side flow and also influences the flow at the back door region. The uneven flow around the wheel and back of vehicle creates low pressure envelope. The side flow disturbance percolates to the rear end flow. Due to uneven flow at the rear and the side, the air flow velocity at the rear side of the vehicle decreases. The decrease of the air flow velocity creates a larger wake area at the rear door region. The abrupt uneven air flow at the back side of vehicle creates a bigger low pressure envelope. Hence in turns leads to higher drag and lesser fuel efficiency.
[008] Vehicle has several outer parts which contribute in the aerodynamic drag of the vehicle. For example, upper exterior parts contribute 45% of the total drag, underbody of the vehicle contributes 30% of the total drag, and wheels of the vehicle contribute 25% of the total drag. The wheels of the vehicle are also responsible for a significant amount of the total aerodynamic drag of passenger vehicles. The wheel and its housing contribute 25% the aerodynamic drag. Also Underbody and Cooling flow is influenced by wheel and wheel-house aerodynamics. Therefore, an improvement in the aerodynamic drag of the wheel can improve the complete aerodynamics of the vehicle.
[009] In view of the above, it is beneficial to have an apparatus that reduces the aerodynamic drag of the wheel for improving the aerodynamic drag of vehicle and improving the fuel efficiency of the vehicle. Therefore, there is a need in the art to provide a structure or a system that is more simple and inexpensive, and which can be placed in the vehicle to reduce the aerodynamic drag of the wheel to improve the aerodynamic drag of the vehicle.
OBJECTS OF THE INVENTION:
[0010] The principal object of the present invention is to provide an apparatus for reducing aerodynamic drag in front wheel of the vehicle.
[0011] Another object of the present subject matter is to provide an apparatus in front overhanging area of the vehicle to directionalize exterior air flow towards rear of the front wheel to reduce wake region for improving the aerodynamic drag of the front wheel.
[0012] Another object of the present subject matter is to provide an apparatus in the form of duct or tube in front part of the vehicle to direct the exterior air flow towards the rear of the front wheel.
[0013] Another object of the present invention is to increase air flow towards back side of the vehicle to diminish the pressure difference between the front and rear of vehicle.
[0014] Another object of the present invention is to reduce the aerodynamic drag of the vehicle to enhance the fuel economy of the vehicle.
[0015] Yet another object of the present invention is to provide uniform flow of air across front wheel of the vehicle and decreases in the aerodynamic drag.
[0016] Yet another object of the present invention is to provide a simple and inexpensive apparatus for reducing wake region in front wheel and improving the aerodynamic drag of the vehicle.
SUMMARY OF THE INVENTION:
[0017] The subject matter disclosed herein relates to an apparatus to improve flow of air at rear of front wheel to reduce wake area at the rear of the front wheels. The apparatus reduces wheel and wheel-house drag forces and its interaction with underbody and cooling flow. The present apparatus improves aerodynamic drag of the vehicle by reducing the wake area at the rear of the front wheels. The apparatus is a fluid duct which directionalizes the air flow towards the rear of front wheel. The fluid duct is provided in front overhanging area which has engine of the vehicle for directionalizing flow of exterior air towards the rear of the front wheel. The fluid duct has a fluid inlet at front end and a fluid outlet at rear end. The fluid inlet is provided in front of the vehicle to receive the exterior air. The fluid outlet is positioned in the wheel well. Further, the fluid outlet is positioned just above the rear of the front wheel to exhaust the directionalized air flow at high pressure. The fluid duct receives the exterior air from the fluid inlet. The fluid duct directionalizes the received exterior air towards the rear of the front wheel through fluid outlet. The directionalized air flow reduces the wake area of the front wheel and improves the aerodynamic drag of the vehicle. Due to reduction in wake area, the air flow around the wheel smoothens and a uniform air flow at the side body near the fender region of the vehicle is achieved. The reduction in wake area of the front wheel, the drag along the front wheel reduces as well as there is enough air flow traveling towards the back door without disturbance that it increases the flow towards the back of vehicle.
[0018] In order to further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit scope of the present subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0020] Fig. 1 illustrates air flow along the vehicle;
[0021] Fig. 2 illustrates an apparatus in front overhanging portion of the vehicle to reduce wake region in rear of front wheel, in accordance in accordance with an embodiment of the present subject matter;
[0022] Fig. 3 illustrates structure of the apparatus for reducing wake region in rear of front wheel, in accordance with an embodiment of the present subject matter;
[0023] Fig. 4 illustrates top view of the apparatus, in accordance with an embodiment of the present subject matter;
[0024] Fig. 5 illustrates a graph explaining normalized drag results of the present invention, in accordance with an embodiment of the present subject matter;
[0025] Fig. 6 illustrates Computational fluid dynamics (CFD) analysis of drag contour of the present invention, in accordance with an embodiment of the present subject matter;
[0026] Fig. 7 illustrates Computational fluid dynamics (CFD) analysis of pressure contour of the present invention, in accordance with an embodiment of the present subject matter; and
[0027] Fig. 8 illustrates Computational fluid dynamics (CFD) analysis of velocity contour of the present invention, in accordance with an embodiment of the present subject matter.
[0028] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0029] The subject matter disclosed herein relates to an apparatus to improve flow of air at rear of front wheel to reduce wake area at the rear of the front wheels. The apparatus reduces wheel and wheel-house drag forces and its interaction with underbody and cooling flow. The present apparatus improves aerodynamic drag of the vehicle by reducing the wake area at the rear of the front wheels. The apparatus is a fluid duct which directionalizes the air flow towards the rear of front wheel. The fluid duct is provided in front overhanging area which has engine of the vehicle for directionalizing flow of exterior air towards the rear of the front wheel. The fluid duct has a fluid inlet at front end and a fluid outlet at rear end. The fluid inlet is provided in front of the vehicle to receive the exterior air. The fluid outlet is positioned in the wheel well. Further, the fluid outlet is positioned just above the rear of the front wheel to exhaust the directionalized air flow at high pressure. The fluid duct receives the exterior air from the fluid inlet. The fluid duct directionalizes the received exterior air towards the rear of the front wheel through fluid outlet. The directionalized air flow reduces the wake area of the front wheel and improves the aerodynamic drag of the vehicle. Due to reduction in wake area, the air flow around the wheel smoothens and a uniform air flow at the side body near the fender region of the vehicle is achieved. The reduction in wake area of the front wheel, the drag along the front wheel reduces as well as there is enough air flow traveling towards the back door without disturbance that it increases the flow towards the back of vehicle.
[0030] Further, reduction in wake area of the front wheel and increase in air flow towards the back side of the vehicle diminishes the pressure difference between the front and rear of vehicle. Resultantly, the aerodynamic drag of the vehicle is reduced which enhances the fuel economy of the vehicle.
[0031] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures.
[0032] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0033] Fig. 2 illustrates placement of an apparatus in front part of the vehicle for reducing wake area in rear of the front wheel, in accordance with the present subject matter. The vehicle 201 has rear, side and front portion 202. The front portion 202 of the vehicle 201 has an engine compartment and other equipment, such as radiator, ECU, battery, apron members of the vehicle. At the front end, a bumper cover is provided along with casings for headlights. An apparatus 204 is provided at the front portion 202 of the vehicle 201. The apparatus 204 is a hollow fluid duct (herein after apparatus and fluid duct may be interchangeably referred as 204) which allows passage of exterior air from one end to other end. The fluid duct 204 is provided in front overhanging area 202, i.e., engine compartment of the vehicle 201 for directionalizing flow of exterior air towards rear 209 of front wheel 208. The fluid duct 204 is positioned longitudinally along the length of the front overhanging area 202 of the vehicle 201. The fluid duct 204 has a fluid inlet 205 at front end and a fluid outlet 206 at rear end. The fluid inlet 205 is provided in front end of the vehicle to receive the exterior air from environment. An aesthetic grill opening is provided in front of the fluid inlet 205 in the front end of the vehicle. The fluid outlet 206 opens in wheel well of the front vehicle. Further, the fluid outlet 206 is positioned just above the rear 209 of the front wheel 208 in wheel well to exhaust the directionalized exterior air flow towards wake area of the front wheel. The fluid duct 204 receives the exterior air from the fluid inlet 205 and exhausts the directionalized air flow from the fluid outlet 206 towards the rear 209 of the front wheel 208 from upper side. The pressure of the directionalized exterior air flow reduces the wake area of the front wheel 208 and improves the wheel drag of the front wheel 208. Similar apparatus is provided on the other side of the vehicle to reduce the wake area of another front wheel of the vehicle. In order to reduce the complexity of the subject matter, the apparatus at one side is explained in detail. Due to reduction in wake area, the air flow around the wheel smoothens and a uniform air flow at the side body near the fender region of the vehicle is achieved. The reduction in wake area of the front wheel 208. The drag along the front wheel 208 reduces as well as there is enough flow traveling towards the back door without disturbance that it increases the flow towards the back of vehicle.
[0034] Fig. 3 illustrates structure of the apparatus or fluid duct for directionalizing the flow of exterior air, in accordance with the present subject matter. The fluid duct 204 has the fluid inlet 205 at the front side and the fluid outlet 206 at the rear side. The front part of the fluid inlet 205 is covered with a grill having plurality of openings to allow passage of exterior air inside the fluid duct 204. The fluid duct 204 has hollow cavity like a channel to directionalize the flow of inlet exterior air. The fluid duct 204 may has constant cross section along its length. Further, the fluid inlet 205 and the fluid outlet 206 may have same hollow cross section area. The cross section area of the fluid inlet 205 and fluid outlet 206 may vary as per the requirements, specially, as per geometry of the vehicle. The air pressure inside the fluid duct 204 may be increased and decreased, as per the requirement, by changing the cross section area of the fluid inlet 205 and the fluid outlet 206. Further, cross section area of the fluid duct 204 can be increased or decreased to change the air flow pressure. Preferably, the fluid inlet 205 has bigger cross section than cross section of the fluid outlet 206 to intake more air and release the air from the fluid outlet 206 at a high pressure. The fluid duct 204 has curved flow path to directionalize the air flow and give high flow pressure to the air towards its target. Further, the fluid duct 204 has curved profile according to curvature of the wheel at upper side. The curved profile of the fluid duct 204 helps to increase the flow pressure of the air inside the fluid duct. Further, the fluid outlet 206 releases the directionalized air from the upper side towards the wake area present at the rear of the front wheel with high pressure to remove the wake area.
[0035] The fluid duct 204 directionalized the air flow to reduce the wake region/area which is low pressure zone in the wheel well near the rear 209 of the front wheels 209. Due to reduction in wake area, the air flow around the wheel smoothens and there is uniform air flow at the side body near the fender region of the vehicle 201. The reduction in wheel wake area reduces the drag due to wheel. Further, enough air flow is traveling towards the back door without disturbance that increases the air flow towards the back side of vehicle. The air flow has high velocity at the back door region which tends to decrease the wake size at the back side and leads to higher back door pressure. The front door and the back door have low pressure difference and uniform flow across front wheel/tire decreases the aerodynamic drag of the wheel.
[0036] Fig. 4 illustrates the top view of the apparatus, in accordance with the present subject matter. The fluid duct 204 gives a directionalized flow 301 to inlet air which increases its pressure and releases the directionalized air flow from a vertical angle with high pressure towards the wake area of the front wheel.
[0037] Fig. 5 illustrates a graph explaining normalized drag results of the present invention, in accordance with an embodiment of the present subject matter. The present apparatus 204 improves the aerodynamic drag coefficient of the vehicle. After implementing, the fluid duct 204 in the vehicle 0.987 normalized drag coefficient is achieved. Table 1 illustrates the comparison of normalized drag coefficient of the present invention with the prior art.
Models Normalized Drag
Existing model Drag 1.000
Inventive design model drag 0.987

[0038] As illustrated from the graph shown in the figure 5, the normalized drag coefficient of the present invention is better than the existing prior arts.
[0039] Fig. 6 illustrates Computational fluid dynamics (CFD) analysis of drag contour of the present invention, in accordance with an embodiment of the present subject matter. The present figure shows CFD analysis of drag contours between the existing vehicle 601 and the vehicle 601a having fluid duct. As illustrated from the figure 6, the existing vehicle 601 has high wheel drag 602 and high drag 603 at back door region and rear wheel region. The vehicle 601a having present fluid duct shows better results during CFD analysis in comparison to existing vehicle. The vehicle 601a has low front wheel drag 602a and low drag 603a at back door region and rear wheel region. The vehicle 601 has more reddish area as comparison to the vehicle 601a.
[0040] Fig. 7 illustrates Computational fluid dynamics (CFD) analysis of pressure contour of the present invention, in accordance with an embodiment of the present subject matter. The present figure shows CFD analysis of pressure contours along the surfaces of the vehicle. Further, the figure 7 illustrates a comparison of pressure contours between the existing vehicle 701 and the vehicle 701a having present fluid duct. As illustrated from the figure 7, the existing vehicle 701 has very low pressure at rear side of the front wheel as indicated by 702. Further, the existing vehicle 701 has low pressure at the back side of the vehicle as indicated by 703. On the other hand side, the vehicle 701a having present fluid duct shows better results as compared to existing vehicle 701. The vehicle 701a has high pressure at rear side of the front wheel as indicated by 702a. Similarly, the back side region of the vehicle 701a has comparatively high pressure, as indicated by 703a.
[0041] Fig. 8 illustrates Computational fluid dynamics (CFD) analysis of velocity contours of the present invention, in accordance with an embodiment of the present subject matter. The directionalizing flow of inlet air from the fluid duct 204 improves the wake area (i.e., low pressure zone) in the rear of front wheels. Due to reduction in wake area, the air flow around the wheels smoothens and there is uniform flow at the side body near the fender region of the vehicle. The present figure illustrates the velocity contours at side and back side of the vehicle. Further, the present figures illustrates the comparison of the velocity contours between the existing vehicle 801 and the vehicle 801a having present fluid duct 204. The air flow has lesser velocity at the side and rear of the vehicle as indicated by 802 and 804 respectively, in the existing vehicle 801. On the other hand, the vehicle 801a has improved air flow velocity as compared to existing vehicle 801. The air flow has high velocity near the side and rear end of the vehicle 801a as indicated by 802a and 803a, respectively.
[0042] It is easy to manufacture and assemble the present fluid duct in front portion of the vehicle. The present fluid duct directionalized the flow of exterior air to reduce the wake area (i.e., low pressure zone) in the rear of front wheels. Due to reduction in wake area, the air flow around the wheel smoothens and there is uniform air flow at the side body near the fender region of the vehicle (as illustrated in figure 8). Because of reduction in wheel wake area, the wheel drag reduces as well as there is enough air flow traveling towards the back door without disturbance that it increases the air flow towards the back door of the vehicle. The high velocity air flow at the back door region and higher velocity tends to decrease the wake size and leads to higher back door pressure. Due to lesser front and back door pressure difference and uniform flow across front wheel the aerodynamic drag decreases and leads to enhanced fuel efficiency.
[0043] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. Plural structural components or steps can be provided by a single integrated structure or step. Alternatively, a single integrated structure or step might be divided into separate plural components or steps. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0044] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.