What Speed Improvement Do Aerofoils Give to an F1 Car - Coursework Example

INTRODUCTION The design F1 cars are such that a down force s created as a result of the aerodynamics of the F1 car (Anderson, 2004). The creation of a down force gives the F1 car the ability to travel at much higher speed as compared the speed the ordinary car can travel at especially at the time of negotiation of corners. This is because of the increased vertical force that acts on the tires thus ensuring increased grip. The same principal in applied in the design of aerofoil of aircrafts even though here the force is in the reverse direction and as a result the an upward force is generated that lifts up the aircraft as opposed to what happens in F1 cars where a down force is created as a result of the aerofoil being created in the opposite direction (Clancy, 1975). The phenomenon experienced in the aerofoil of a car is referred to as aerodynamic grip which is different from mechanical grip which depends on the car mass repartition, the type of tires used on the car and the car suspension. Creation of a down force by passive elements is always be accompanied by increased drag force and an optimum design will always aim at having a compromise of the two (Bertin, J. J. and Smith, M. L., 2001).The aerodynamic set ups of an F1 car can be varied to suite the race tracks as with regards to the track length in the straights and the nature of corners on the track. Sometimes drivers may effect some setting while driving. The created force results from the flow of air at the lower side and the upper side and the lower side of the F1 car and with the increase of aerodynamic force being proportional to the square of the velocity it follows that the down force will increase proportionate to the speed of the car with there being a minimum speed requirement from where there can be a significant down force. By having aerodynamic devices on cars could result to instability in the car where small change in the angle of attack of the aerofoil of raising the car may result to high variation in the down force generated ad this could even result to the car being lifted from the ground (Houghton, 2006). The circumstances that can lead to such scenario is when a car encounters a bump or by a car strip streaming over a crest and these situations may result to a disaster. A typical case of such a scenario is the spectacular flipping of Mercedez-Benz CLR being driven by Peter Dumbreck as he closely chased a competitor’s car on a rump in the 1999 Le Mans 24 hours. The body shape of F1 cars and the incorporation of airfoils are the two major components that results to a down force being generated and thus making the car to be able to move at very high speed even during corner negotiation. The F1 race regulation does not allow the adjustment of any of aerodynamic devices by the driver during the race except at the pit stop. The expression of a down force for a car aerofoil is : Where: D is the down force given in Newtons WS is the wingspan in metres H is the height in metres = gives the angle of attack in degrees F = is lift coefficient ρ =is air density in kg/m³ V = velocity in m/s The upper part of a car is usually tapered so as to be able to cut into the air and this puts wind resistance to a minimal. Other bodyworks maybe included at the upper side of the car to facilitate smooth flow of air so as to access the devices that are to generate the down force such as the air body tunnels, the wings or spoilers. In general the shape of ordinary car is very similar to the aerofoil of an aircraft where the air flowing on top is at a higher speed while that flowing under the car is of relatively lower speed and this brings about pressure difference and thus resulting into the car experiencing a lift. A device that has a large surface area will experience a greater down force and the drag will also be proportional to the cross-sectional area being swept by device. The aspect ratio is important in the description of the aerofoil and is given by AR=b squared/s, where AR stands for aspect ratio, b= span squared and s being the area of the wing. If the angle of attack of the aerofoil is increased it results to an increase in the downforce and this in turn will increase the pressure that will be exerted on the rear tires as well as the drag force on the F1 car. Front aerofoil The front aerofoil helps in both the generation of a down force that enhances the grip of the front tires and also help in optimizing of airflow to the car body as a whole. The front aerofoil in open wheeled cars will always be modified constantly by use of the data that is being gathered from race to race thus resulting to customization to particular circuit. In many of F1 car races the aerofoil design is such adjustment making is possible in the time of servicing when a race is in progress. Rear aerofoil The airflow on the front airfoil influences the flow of air on the rear airfoil. Other components such as the helmet of the driver, side pods, the front wheels and the exhausts also have influence on the rear airfoil airflow performance. Due these influences by several components of the car the rear airfoil is found to be less efficient when compared o the front airfoil. But with all these things affecting its performance the rear airfoil is expected to produce more than double the downforce that is generated by the front airfoil. For these to be made a reality the aspect ratio is increased for this rear airfoil and sometimes two or even more elements are put into use so as to have increased downforce. It is possible to adjust the rear airfoil at the service point either before the racing begins or in the course of the race just like in the case of the front airfoil. It is also regarded as the component of the car that need close attention. Discussion Taking the standard maximum width of F1 car to be 1.8m as shown on the image and the length of 1.8m being equal to 157 pixels. 1m = 157/1.8 = 87.22pi Now by use of this relationship s is possible to calculate the dimension of the F1 car Width of front airfoil is 35pi= 35/87.22= 0.4m Area of front airfoil = 0.4 x 1.8 = 0.72m2 Length of back airfoil = 73pi = 73/87.22= 0.84 Width of back airfoil = 39pi = 39/87.22 = 0.45 Area of back airfoil = 0.84 x 0.45 = 0.378 The down force is given by D = C Calculation of maximum speed for the different conditions The maximum velocity is reached at the point when the centrifugal (sideforce ) just goes beyond the friction force between the F1 car tires and the racing track. Friction force =  Centrifugal force =  At the maximum speed of F1 car =  By simplifying =  At  r=50  = 18.52971 When the same argument is applied to other conditions the results will be as summarized in the table. Table 3 Radius of corner µ 50 100 200 500 0.7 18.52971 26.20496 37.05941 58.59607 0.4 14.00714 19.80909 28.01428 44.29447 0.9 21.01071 29.71363 42.02142 66.4417 0.1 7.003571 9.904544 14.00714 22.14723 Calculating maximum speed when airfoil has been added As a result of airfoil a down force will act on the F1 car and this is factored in the calculation D = C =  =  The areas A1 and A2 have been earlier calculated as 0.72 and 0.378 The coefficients for the airfoils are 0.6 and 1.9 respectively =  =  =  =  =  At  r=50 the same formula is applied to for the other conditions and the the results will be as summarized in the table 2. Table 2 radius of corner µ $50 100 200 500 0.7 19.59357 29.50699 48.77001 #NUM! 0.4 14.81135 22.30519 36.86666 #NUM! 0.9 22.21702 33.45778 55.29999 #NUM! 0.1 7.405674 11.15259 18.43333 #NUM! Graph for maximum speed with no airfoils Graph for maximum speed with airfoils Conclusion The principles that are used to obtain the unique characteristics of f1 cars has been defined clearly in this paper. The airfoils are able to increase the down force acting on the car if the car is moving at considerably high speed. From able 2 results it is clear that drivers can negotiate corners which are less sharp at higher speed with no danger of the car slipping but when the corner is sharp the safe speed of negotiating a corners is lowered. At 500m radius corners the F1 car is capable of moving at as much speed as that on a straight race course. The car will not slip at the rear and front tires simultaneously. What determines the tires that slips first is the fraction of weight that is acting on the tires (which is determined by where the centre of gravity of the car is located) and the down force generated by each of two airfoils. References Anderson, John D. (2004), Introduction to Flight (5th ed.), McGraw-Hill, pp. 352–361, §5.19, ISBN 0-07-282569-3 Bertin, J. J. and Smith, M. L. (2001). Aerodynamics for Engineers (4th ed.). Prentice Hall. Clancy, L.J. (1975), Aerodynamics, Pitman Publishing Limited, London ISBN 0-273-01120-0 Houghton, E.L. and Carpenter, P.W.(2006)- Fifth Edition Aerodynamics for Engineering Students Piercy N.A.V.(1955)-Aerodynamics. Read More

The body shape of F1 cars and the incorporation of airfoils are the two major components that results to a down force being generated and thus making the car to be able to move at very high speed even during corner negotiation. The F1 race regulation does not allow the adjustment of any of aerodynamic devices by the driver during the race except at the pit stop. The expression of a down force for a car aerofoil is : Where: D is the down force given in Newtons WS is the wingspan in metres H is the height in metres = gives the angle of attack in degrees F = is lift coefficient ρ =is air density in kg/m³ V = velocity in m/s The upper part of a car is usually tapered so as to be able to cut into the air and this puts wind resistance to a minimal.

Other bodyworks maybe included at the upper side of the car to facilitate smooth flow of air so as to access the devices that are to generate the down force such as the air body tunnels, the wings or spoilers. In general the shape of ordinary car is very similar to the aerofoil of an aircraft where the air flowing on top is at a higher speed while that flowing under the car is of relatively lower speed and this brings about pressure difference and thus resulting into the car experiencing a lift.

A device that has a large surface area will experience a greater down force and the drag will also be proportional to the cross-sectional area being swept by device. The aspect ratio is important in the description of the aerofoil and is given by AR=b squared/s, where AR stands for aspect ratio, b= span squared and s being the area of the wing. If the angle of attack of the aerofoil is increased it results to an increase in the downforce and this in turn will increase the pressure that will be exerted on the rear tires as well as the drag force on the F1 car.

Front aerofoil The front aerofoil helps in both the generation of a down force that enhances the grip of the front tires and also help in optimizing of airflow to the car body as a whole. The front aerofoil in open wheeled cars will always be modified constantly by use of the data that is being gathered from race to race thus resulting to customization to particular circuit. In many of F1 car races the aerofoil design is such adjustment making is possible in the time of servicing when a race is in progress.

Rear aerofoil The airflow on the front airfoil influences the flow of air on the rear airfoil. Other components such as the helmet of the driver, side pods, the front wheels and the exhausts also have influence on the rear airfoil airflow performance. Due these influences by several components of the car the rear airfoil is found to be less efficient when compared o the front airfoil. But with all these things affecting its performance the rear airfoil is expected to produce more than double the downforce that is generated by the front airfoil.

For these to be made a reality the aspect ratio is increased for this rear airfoil and sometimes two or even more elements are put into use so as to have increased downforce. It is possible to adjust the rear airfoil at the service point either before the racing begins or in the course of the race just like in the case of the front airfoil. It is also regarded as the component of the car that need close attention. Discussion Taking the standard maximum width of F1 car to be 1.8m as shown on the image and the length of 1.

8m being equal to 157 pixels. 1m = 157/1.8 = 87.22pi Now by use of this relationship s is possible to calculate the dimension of the F1 car Width of front airfoil is 35pi= 35/87.22= 0.4m Area of front airfoil = 0.4 x 1.8 = 0.72m2 Length of back airfoil = 73pi = 73/87.22= 0.84 Width of back airfoil = 39pi = 39/87.22 = 0.45 Area of back airfoil = 0.84 x 0.45 = 0.378 The down force is given by D = C Calculation of maximum speed for the different conditions The maximum velocity is reached at the point when the centrifugal (sideforce ) just goes beyond the friction force between the F1 car tires and the racing track.

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