Science Behind F1 Aerodynamic Features.
Table of Contents
.0 Science Behind F1 Aerodynamic Features......................................................1
.1 Bernoulli's Equation.................................................................................1
.2 Drag....................................................................................................2
.3 Downforce.............................................................................................5
2.0 History of Aerodynamic Features - Momentous Design Innovations..............6
3.0 Features of the Front Half of the F1 Vehicle..................................................6
3.1 Front Wing...........................................................................................6
3.2 Wheels.................................................................................................8
3.3 Suspension............................................................................................9
3.4 Barge Boards.......................................................................................10
3.5 Brake Cooling......................................................................................11
4.0 Features of the Rear Half of the F1 Vehicle.................................................11
4.1 Rear Wing...........................................................................................11
4.2 Endplates............................................................................................13
4.3 Diffuser..............................................................................................14
4.4 Chimneys............................................................................................15
4.5 Flip-ups..............................................................................................17
5.0 Testing........................................................................................................17
5.1 Computational Fluid Dynamics (CFD).......................................................17
5.2 Wind-Tunnels......................................................................................18
6.0 Technical Regulations Affecting Aerodynamic Features..............................19
7.0 Concluding Remarks - Predictions for the Future.......................................20
References.............................................................................................................22
.0 Science Behind F1 Aerodynamic Features
Engineered with perfection, the loud and aggressive Formula One (F1) racecar is the ultimate racing machine. Its reputation has been defined by its amazing speed and handling characteristics, which are for the most part, a product of its aerodynamic features. The success of these features relies primarily on the appropriate and efficient harnessing of drag and downforce - both of which are ruled by physical principles explained by Bernoulli's equation.
.1 Bernoulli's Equation
Investigated in the early 1700s by Daniel Bernoulli2, his equation defines the physical laws upon which most aerodynamic concepts exist. This now famous equation is absolutely fundamental to the study of airflows. Every attempt to improve the way an F1 car pushes its way through molecules of air is governed by this natural relationship between fluid (gas or liquid) speed and pressure. There are several forms of Bernoulli's equation, three of which are discussed, in the succeeding paragraphs: flow along a single streamline, flow along many streamlines, and flow along an airfoil. All three equations were derived using several assumptions, perhaps the most significant being that air density does not change with pressure (i.e. air remains incompressible). Therefore they can only be applied to subsonic situations. Being that F1 cars travel much slower than Mach 1, these equations can be used to give very accurate results.1
Low speed fluid flow along single or multiple streamlines is interpreted in Figure 1. The presumptions regarding the application of Bernoulli's equation to this scenario are listed in the figure. In this situation, there exists a relationship between velocity, density and pressure. As a single streamline of fluid flows through a tube with changing cross-sectional area (i.e. an F1 air inlet), its velocity decreases from station one to two and its total pressure equals a constant. With multiple streamlines, the total pressure equals the same constant along each streamline. However, this is only the case if height differences between the streamlines are negligible. Otherwise, each streamline has a unique total pressure.
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Figure 1: Mathematical and pictorial explanation of Bernoulli's Equation as applied to fluid flow through a tube with changing cross-sectional area.2
As applied to flow along low speed airfoils (i.e. F1 downforce wings), airflow is incompressible and its density remains constant. Bernoulli's equation then reduces to a simple relation between velocity static pressure.1
(pressure) + 0.5(density)*(velocity)2 = constant
This equation implies that an increase in pressure must be accompanied by a decrease in velocity, and vice versa. Integrating the static pressure along the entire surface of an airfoil gives the total aerodynamic force on a body. Components of lift and drag can be determined by breaking this force down.
In order to discuss lift and downforce, it may be helpful to provide an additional explanation of the relationship that occurs with the above form of Bernoulli's equation. If a fluid flows around an object at different speeds, the slower moving fluid will exert more pressure on the object than the faster moving fluid. The object will then be forced toward the faster moving fluid.8 A product of this event is either lift or downforce, each of which is dependent upon the positioning of the wing's longer chord length. Lift occurs when the longer chord length is upward and downforce occurs when it is downward. The scenarios for lift and downforce are depicted in Figures 2 and 6, respectively.
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Figure 2: Lift according to the application of Bernoulli's Equation
.2 Drag
The remarkable speed of the F1 racecar is achieved from the careful combination of its powerful engine and expertly crafted aerodynamic body features. In the early years of F1 design, the engine was the primary variable in determining the racing success of a car. Applicable engine technology had far exceeded the maturity of vehicle aerodynamics. Those historic years embodied a simple algorithm. Speed was nearly a direct function of horsepower. Although still improving almost annually, engine performance levels among the cars of each racing season today have comparable performance - record speed achievements now hinge on a different design issue - aerodynamics and drag plays a major role. F1 aerodynamics engineer, Will Gray, has noted that "Top speed is determined other factors [car weight, fuel strategy, and good low-end engine power], but the main factor which separates the victors from the valiants in this area is aerodynamic performance - too much drag and you're pulling unwanted air along with you." 3
One form of drag occurs as air particles pass over a car's surfaces and the layers of particles closest to the surface adhere. The layer above these attached particles slides over them, but is consequently slowed down by the non-moving particles on the surface. The layers above this slowed layer move faster. As the layers get further away from the surface, they slow less and less until they flow at the free-stream speed. The area of slow speed, called the boundary layer, appears on every surface, and causes one of the three types of drag, Skin Friction Drag.
The force required to shift the molecules out of the way creates a second type of drag, Form Drag. Due to this phenomenon, the smaller the frontal area of a vehicle, the smaller the area of molecules that must be shifted, and thus the less energy required to push through the air. With less engine effort being taken up in the moving air, more will go into moving the car along the track, and for a given engine power, the car will travel faster. Another factor that plays a role in aerodynamic efficiency is the shape of the ...
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The force required to shift the molecules out of the way creates a second type of drag, Form Drag. Due to this phenomenon, the smaller the frontal area of a vehicle, the smaller the area of molecules that must be shifted, and thus the less energy required to push through the air. With less engine effort being taken up in the moving air, more will go into moving the car along the track, and for a given engine power, the car will travel faster. Another factor that plays a role in aerodynamic efficiency is the shape of the car's surfaces. The shape over which air molecules must flow determines how easily the molecules can be shifted. Air prefers to follow a surface rather than to separate from one. Interestingly, researchers of aerodynamics have found the 'teardrop' shape, round at the front and pointed at the back, to be most efficient at propelling through air while providing a suitable surface for the air to easily move across. With this shape there is little or no separation. It is important to note that sharp frontal areas, rounded ends, sharp curves or sudden directional changes in a shape should be avoided since they tend to cause separation, which increases drag (See Figure 3).
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Figure 3: Comparison of unconstrained fluid flow behaviors over a pointed, circular and teardrop shape
The final type of drag is Induced Drag. It is noted as such because it is caused by or "induced" by the lift on the wings.3 Induced drag is an unfavorable and unavoidable byproduct of lift (or downforce). It occurs on wings of standard or inverted position. In fact, the potential of displaying induced drag exists for all bodies that exhibit opposite pressures on their top and bottom surfaces. Being that air prefers to move from high to low-pressure regions, air from low-pressure regions has a tendency to curl upward around the ends of a wing, for example. It travels up from the high-pressure region to the low-pressure region on the top of the wing and collides with moving low-pressure air (See Figure 4). Wingtip vortices are a result of this situation. These vortices occur on both airplane wings and F1 car wings even though end plates may be used to prevent this type of drag (See Figure 5). It should be noted that the kinetic energy of these turbulent air spirals acts in a direction that is negative relative to the direction of travel intended. In the case of induced drag on F1 cars, the engine must compensate for the losses created by this drag.
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Figure 4: Pressure induced drag - formation of wingtip vortices on aircraft wings
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Figure 5: Induced drag - wingtip vortices on the wings of an F1 car and airplane8
The F1 racecar is a complicated aerodynamic system - composed of skin friction, form and induced drag. Resultantly, aerodynamicists typically find it sufficient to estimate an overall coefficient of drag for these cars. The following equation4, which incorporates the effects of all three drag types, is used to determine this data.
F = 0.5CdAV2, where F - Aerodynamic drag
Cd - Coefficient of drag
D - Air density
A - Frontal area
V - Object velocity
Interestingly, modern F1s are reported to have Cd values of about 0.83 with corresponding CdA[m2] values near 1.2.1 These values are approximately double of those for the modern Ford Sierra, an ordinary family sedan. This is primarily due to three reasons. The first is that regulations specify features that deter from the ability of a designer to achieve relatively low drag coefficients (i.e. open cockpits and running exposed wheels). The second reason is likely due to be the fact that F1 cars rely on a balance between drag and downforce in which drag is often sacrificed for necessary downforce. In order to make up for the speed losses due to drag, engine power is increased if possible. Lastly, unlike family sedans, low fuel consumption is not a paramount concern. Therefore, drag coefficients are allowed to be somewhat large, especially since the importance of other factors (i.e. downforce) takes priority.
.3 Downforce
Downforce, or negative lift, pushes the car onto the track.5 It is accomplished by use of an airfoil mounted such that its longer cord length is facing downward. As air flows over the airfoil, as seen in Figure 6, a low-pressure region is created on the under side of the wing. A high-pressure region then develops on the upper side of the wing, creating a downward force. This pressure difference causes the net downforce.
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Figure 6: Airflow over an F1 downforce wing
Downforce is necessary for maintaining speed through corners.8 Due to the fact that the engine power available today can overcome much of the opposing forces induced by drag, design attention has been focused on first perfecting the downforce properties of a car then addressing drag.
The teardrop shape, previously discussed, displays ideal aerodynamic properties in an unconstrained flow and is well suited for aeronautical applications. However, when this shape is incorporated into the design of an F1 vehicle, it is subjected to constrained flow, which causes different flow behaviors. This is due to the simple fact that these cars are very close to the ground. The presence of the ground prevents the formation of a symmetrical flow pattern (See Figure 4).1 The results of this flow behavior are an unfavorable increased drag coefficient and generation of a very favorable down force. Fortunately, the downforce created is highly valuable and the increased drag can be overcome with array of aerodynamic strategies.
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Figure 7: Unconstrained and constrained fluid flow behaviors displayed respectively, over a teardrop shape
Jordan GP Technical Director, Mike Gascoyne has declared, "Aerodynamics is where the most performance gains can be made, but making these advances in order to be competitive is difficult."6 To gain optimal results, the aerodynamicist must maximize downforce while minimizing drag. Attempting to near this ideal scenario is a complicated task. It is in all actuality a never-ending balancing act involving a plethora of compromises. However, gaining ground in this realm of science is crucial for the development of a competitive car.
2.0 History of Aerodynamic Features - Momentous Design Innovations
Over the last sixty-six years, many aerodynamic feature innovations have been achieved. However, there are several which are most prominent in F1 development history. Making their debut in 1934, German F1 cars demonstrated the streamlining of a car's body to reduce drag. In 1962, the monoque or one-piece chassis was introduced. This innovation was also designed to reduce drag. Shortly afterward, in 1968, the use of wings came about. Hence came the application of the downforce phenomenon with the benefits of increased traction and cornering speed. In the early 1970s, airboxes were placed behind the cockpit in order to increase airflow to the engine and therefore increase the engine's power output. 1978 brought about the advent of ground effects - a controversial success since they caused cars to become dangerously sensitive to road surface obstructions. Essentially what this feature did was turn the entire car into a large, inverted wing, using the side skirts and underbody design to literally glue the car to the track.5 During 1997, "X-wings", sidepod-mounted winglets designed to increase downforce, were introduced only to be banned the following year. There have also been many recent notable advancements made however they will be discussed in the upcoming portions of this paper.
3.0 Features of the Front Half of the F1 Vehicle
3.1 Front Wing
The front wings on the car can produce 25-40% of the cars downforce. Each front aerofoil is made a mainplane (1) running almost the whole width of the car suspended from the nose (4). Onto this are fitted two aerofoil flaps (2), one on each side, which are the adjustable parts of the wing. These flaps are usually made of one piece of carbon fiber, but Ferrari has used two small flaps rather than one large one. On each end of the mainplane there are endplates (3).8
Figure 8:Front wing and nose cone assembly8
The wing flap on either side of the nose cone is asymmetrical. It reduces in height nearer to the nose cone as this allows air to flow into the radiators and to the underfloor aerodynamic aids. If the wing flap maintained it's height right to the nose cone, the radiators would receive less airflow and therefore the engine temperature would rise. The asymmetrical shape also allows a better airflow to the underfloor and the diffuser, increasing downforce. The wing mainplane is often raised in the center. This again allows a slightly better airflow to the underfloor aerodynamics, but it also reduces the wings ride height sensitivity.
Figure 9: Front wing of the 2000 Ferrari8
Over time, as the wheels were moved closer to the chassis, the front wings overlapped the front wheels when viewed from the front. This created unnecessary turbulence in front of the wheels, further reducing aerodynamic efficiency and thus contributing to unwanted drag. To overcome this problem, the top teams made the inside edges of the front wing endplates curved to direct the air towards the chassis and around the wheels. Many teams later introduced sculpted outside edges to the endplates to direct the air around the front wheels. This was often included in the design change some teams introduced to reduce the width of the front wing to give the wheels the same position relative to the wing in previous years. The interaction between the front wheels and the front wing makes it very difficult to come up with the best solution, and consequently almost all of the different teams have come up with different designs.8
Figure 10:End plates deflecting air around tires8
The relationship between the front wing and the track is a delicate one; with the wing generally being more efficient the closer it is to the track. Therefore, the front wing is low to the ground to obtain as much advantage from ground effect as possible, and generally has one full spanning flap. Developments usually concentrate on the profile of the wing, and the use of flaps. However, Ferrari recently angled the leading edge of the wing to form a forward racing V-shape. This comes from flow visualizations on the wing, which shows its suction power is so strong that it pulls air in from angles not straight with the centerline. This means that the air is approaching a normal, straight leading edge at an angle to it, and therefore not working the wing to its full potential. By turning the edge by the correct angle, maximum efficiency will be obtained.
The part of the front wing, which tends to change most in design, is the endplate. The primary function of this feature is to stop the high-pressure air on the top of the wing from being encouraged to roll over the end of the wing to the low-pressure air beneath, causing induced drag. Additionally, the design aim of the endplates is to discourage the dirty air created by the front tire from getting under the floor of the car. Further to these, some teams use 'splitters', which are vertical fences, attached to the undersurface of the front wing, to assist the endplates.3
Figure 11:End plate preventing high-pressure air to join low-pressure air3
3.2 Wheels
The wheels of a formula one car probably induce the most drag of any part of the car. Unfortunately, have yet to be redesigned to reduce aerodynamic drag. Hindering this innovation are certain technical regulations. One such regulation is that the wheels cannot be covered. F1 wheels must to be the shape they are and this causes separation behind them. This separation causes large amounts of form drag. The amount of generated skin friction drag is minimal in comparison. So far, it appears that not much can be done to reduce form drag on the wheels, however teams have used the front wing to try to deflect the oncoming air around the front tires.
Figure 12:Air flow over entire car, specifically drag on tires9
3.3 Suspension
In recent years, suspension members have been streamlined into an aerofoil shape. According to the rules however, they are not allowed to produce downforce, and are simply shaped that way to reduce drag, and to keep the flow heading for the sidepods relatively undisturbed. The suspension arms are a good example, as they are often made in a shape of a wing, although the upper surface is identical to the lower surface. This is done to reduce the drag on the suspension arms as the car travels through the air at high speed. Consider Figure 13. In the lower diagram, A, represents an unstreamlined suspension arm, the lower one, B, a suspension arm with an aerodynamic covering. Both have roughly the same cross sectional area, but the lower case has a drag force ten times less than A.
Figure 13:Suspension member streamlining8
3.4 Barge Boards
These devices were first seen in 1993 and their purpose is to smooth the airflow around the car and into the radiator intakes. They are most commonly mounted between the front wheels and the sidepods (See Figure 14). Their main purpose is to direct relatively clean air into the sidepods. Clean air is from the low section of the front wing where airflow is fairly unaffected by the wing and far away from tires, which may throw stones and debris in to the radiator.
Figure 14: 1993 McLaren barge boards8
Figure 15: Ferrari F1-2000 barge boards5
Since they were first used, they have become much more complicated in their design. Figure 14 shows what they looked like when they were first introduced on the 1993 McLaren. They are slightly curved plates, nothing more. In contrast with the 2000 Ferrari which can be seen in Figure 15. Since then they have become much more complex in shape and likely much more effective with less drag. Most formula1 teams today carry out extensive research and development of aerodynamic efficiency in a wind tunnel. The barge boards and the associated cooling properties are most likely a very high priority on aerodynamic design.
3.5 Brake Cooling
Brake cooling is vital in today's Formula 1, because of the extreme heat produced. Modern racecar brakes can heat up until they are red hot. They can easily be destroyed at such extreme temperatures. This is where aerodynamics comes into play with the addition of small air intakes to bring cooling air to the brakes. They can be seen in the pictures below. These intakes actually change between races, since the braking requirements of each track are quite different.
Figure 16:Brake inlets from 2000 McLaren8
4.0 Features of the Rear Half of the F1Vehicle
4.1 Rear Wing
The rear wing is a crucial component for the performance of a Formula One racecar. These devices contribute to approximately a third of the car's total down force, while only weighing about 7 kg.10 Figure 17 shows a rear wing. Usually the rear wing is comprised of two sets of aerofoils connected to each other by the wing endplates. The wing endplates will be discussed in section 4.2. The upper aerofoil, usually consisting of three elements, provides the most downforce, therefore varied from race to race. The lower aerofoil, usually consisting of two elements, is smaller and provides some downforce. However, the lower aerofoil creates a low-pressure region just below the wing to help the diffuser create more downforce below the car. The diffuser is discussed in section 4.3.
Figure 17: Rear wing of Formula One racecar10
The rear wing is varied from track to track because of the trade off between downforce and drag. More wing angle increases the downforce and produces more drag, thus reducing the cars top speed. So when racing on tracks with long straights and few turns, like Monza, it is better to adjust the wings to have small angles. Conversely, when racing on tracks with many turns and few straights, like Austria, it is better to adjust the wings to have large angles. Figure 18 shows a comparison of wings on the Ferrari F1-2000 for two different tracks. The section on the left shows Michael Schumacher in Austria while the section on the right shows Ruebens Barrichello in Monza. The section on the left clearly shows an increased wing angle compared to the section on the right.
Figure 18: Comparison of wings for different tracks10
Splitting the aerofoil into separate elements as seen in Figure 19 is one way to overcome the flow separation caused by adverse pressure gradients. Multiple wings are used to gain more downforce in the rear wing. Two wings will produce more downforce than one wing, but not twice as much. Figure 20 shows the relationship between the number of airfoils with both the lift coefficient and the lift/drag ratio. The lift coefficient increases and lift/drag ratio decreases when increasing the number of aerofoils. The position of the wings relative to each other is important. If they are too close together, the resultant forces will be in opposite directions and thus cancel each other. Figure 21 shows how the coefficient of lift for the upper and lower wings vary based on their relative position.
Figure 19: Rear wings with separate aerofoil elements13
Figure 20: The effect of using multiple aerofoils1
Figure 21: Effect of separation distance between two aerofoils in the biplane arrangement1
4.2 Endplates
Rear wing endplates are designed with form and function in mind. Because of their form they provide a convenient and sturdy way of mounting wings. The aerodynamic function of these endplates is to prevent air spillage around the wing tips and thus they delay the development of strongly concentrated trailing vortices. Trailing vortex or induced drag is the dominating drag on rear wings. An additional goal of the rear endplates is to help reduce the influence of upflow from the wheels. Figure 22 shows a rear wing endplate on the 2000 season McLaren MP4-15. Figure 23 shows a rear wing endplate on the 2000 season British American Racing BAR-002. There is a U-shaped cutout from the endplate that further alleviates the development of trailing vortices.
Figure 22: Endplates on McLaren MP4-1511
Figure 23: Endplates with U-shaped cutout on BAR-0021
4.3 Diffuser
The diffuser is usually found on each side of the central engine and gearbox fairing and is located behind the rear axle line as seen in Figure 24. As seen in Figure 25, the diffuser consists of many tunnels and splitters. It is designed to carefully guide and control airflow underneath the racecar. Essentially, it creates a suction effect on the rear of the racecar and pulls the car down to the track. The suction effect is a result of Bernoulli's equation, which states (as discussed in section 1.1) that where speed is higher, pressure must be lower. Therefore the pressure below the racecar must be lower than the pressure at the outlet since the speed of the air below the racecar will be higher than the speed of the air at the outlet. Racecar engineers must carefully design the diffuser, since its dimensions are limited by the racing regulations and its angle of convergence is somewhat restricted. If the angle of convergence is too great then the flow will separate because of the adverse pressure gradient.
Figure 24: Diffuser of BMW Williams12
Figure 25: View of tunnels and splitters of Ferrari's diffuser10
4.4 Chimneys
Chimneys are an aerodynamic feature recently debuted during the F1 2000 season. Many of the top teams like McLaren, Ferrari, and BMW Williams have experimented their use. As seen in Figure 26 the chimneys are mounted on the cooling sidepods. The primary function of chimneys is to provide additional cooling to the engine. This is accomplished by creating a pressure gradient. The increase in speed of the air over the chimney creates a low-pressure region that sucks out air from the sidepods to aid the radiators in cooling the engine. Many different versions of chimneys were designed for the 2000 season. Figure 27 shows Ferrari's version of the chimney while Figure 28 shows BMW's version. Ferrari's version is obviously smoother in shape to reduce drag.
Figure 26: Chimneys located on sidepods11
Figure 27: Chimney on Ferrari F1-200010
Figure 28: Chimney on BMW Williams10
4.5 Flip-Ups
Lift due to exposed wheels is a major problem for F1 racecars since regulations prohibit enclosing the wheels within the bodywork. Exposed wheels generate upward lift forces that decrease the downforce created by the wings and other structures. This positive lift may reduce downforce by approximately 11% on a typical F1 track.1 To alleviate this problem, engineers design flip-ups on the rear section of the sidepods, in front of the rear tires. Flip-ups as seen in Figure 29 guide air over the rear wheels while creating some downforce.
Figure 29: Examples of flip-ups10
5.0 Testing
5.1 Computational Fluid Dynamics
Computational fluid dynamics (CFD) is nearing a period of rapid development regarding its applications to racing car aerodynamics. Although CFD is considered to be in a state of infancy by some, computers equipped with CFD software are already being used to investigate water and oil cooling, and even to determine the appropriate drag and downforce properties to yield the ideal lap times at particular tracks.3 CFD analysis is also used to study vortex formation caused by induced drag on downforce wings (See Figure 30). Additionally, CFD techniques enable F1 airfoils to be fashioned to produce desired pressure distribution in the realistic conditions of ground and bodywork proximity.1 However, in other aspects of F1 design, the capabilities of CFD are currently lacking, particularly where rotating wheels and moving grounds are involved.
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Figure 30: CFD study of vortex formation on an F1 downforce wing
There are two basic mathematical methods (each with its strengths and weaknesses) that can be used with the presently available commercial software packages. The first is a linear method and the second is nonlinear, including the option to apply an Euler's, Reynolds Averaged Navier-Stokes or an instable flow method. These methods are quite powerful and when used in conjunction with validating experimental data, they can prove to be quite useful. However, despite their effectiveness, the simple fact that CFD results must be validated means that the importance of wind-tunnel studies remains high.
5.2 Wind-Tunnels
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Figure 31: Wind-tunnel facility and testing in progress3
To investigate the aerodynamic features of an F1 car, engineers conduct extensive amounts of careful wind-tunnel testing. As of yet, this method can be considered to be the most accurate and understood testing strategy available. An example of a wind-tunnel facility and testing in progress can be seen in Figure 31.
There are two types of wind-tunnel configurations: closed-return and open return. The closed-type is the most modern and common and is therefore most often used for F1 testing. For F1 testing, certain special features have been included in the design of these facilities. For example, the floors of these wind tunnels are replaced with "rolling roads" (fancy conveyor belts that run at the same speed as the wind) and sophisticated boundary control systems designed to simulate the fact that the car rolls over the ground. It is important to note that these rolling roads and boundary layer control systems are essential for racing car work and are in fact a science in themselves.
The top teams have in the order of 10 to 30 people working full time on aerodynamic research. The models used range from one quarter to half scale and are tested in wind tunnels for up to 300 days per year per team.3 Most of this time is exhausted by working with scale models. These models are typically constructed of different materials and via different methods than the actual cars. However, they are designed to simulate both the internal and external shape of the cars while enabling the teams to change the design of the model shape more simply than would be possible on a miniature replica of the real car.
6.0 Technical Regulations Affecting Aerodynamic Features
Many appearance similarities can be drawn between the F1 cars of today. This is largely due to the numerous regulations imposed on their design. For the racing season of the year 2000, there were 20 different regulation articles. Although the seasonal F1 design regulations deal with an array of issues, for example fuel specifications, many have a direct effect on the aerodynamic characteristics that a car may have. This year the majority of such requirements fell under five particular articles: Bodywork & Dimensions, Wheels & Tires, Cockpit, Brake System, and Safety Equipment. Specific issues addressed under these articles are as follows.
*
* Overall width
* Width ahead of the rear wheel center-line
* Width beyond the rear wheel center line
* Overall height
* Front bodywork height
* Height in front of the rear wheels
* Height between the rear wheels
* Height behind the rear wheel center line
* Bodywork around the front wheels
* Bodywork facing the ground
* Skid block
* Overhangs
* Aerodynamic influence
* Upper bodywork
* Wheels and tires
* Air ducts
* Cockpit
* Rear view mirrors
*
New amendments are made to F1 design specifications each year. Although they are typically imposed for the sake of improving safety, often they affect the aerodynamic potential of a car. This sacrifice of performance is deemed necessary and highly justifiable. Over the history of F1 racing, both drivers and spectators have lost their lives as a result of design failures. Resultantly, there have been many instances in which the Federation Internationale de l'Automobile (FIA) has imposed new regulations. For example, in 1983, ground effects, due to the instability they caused cars, were banned and all F1s were ordered to have flat undersides.7 Speed without efficient control leads to disaster in F1 racing. And designs that disable driver control are banned. Over the years, the FIA has been compelled to enact many additional design regulations. They are necessary because they reduce the occurrence of unsound designs showing up on the racetrack. It is well known that an engineer can design a car to reach almost infinite speeds but without offering the driver a reasonable amount of control, the design is incomplete.
7.0 Concluding Remarks - Predictions for the Future
Forecasts have been made regarding the changes we might see in F1 design. It has been reported that additional attention will be given to helmet design. Driver's helmets can be exposed to airflows in excess of 200mph and resultantly experience buffetting effects, which hinder aerodynamics and can jeopardize driver safety.8 Engineers have tried to solve this problem by mounting aerodynamic aids onto helmets. According to a helmet designer at Simpson Race Products (SRP), aerodynamic aids perform three separate functions:
. Preventing helmets from lifting at high speeds
2. Stopping the buffeting effect (on the driver's head and neck)
3. Cleaning up the airflow from the helmet going back to the car's rear wing
SRP also claims that their fan-shaped device has the effect of adding 12 lbs of downforce at 220mph.8 A helmet with this device may be viewed in Figure 32.
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Figure 32: Simpson Race Products helmet with aerodynamic device
There has also been speculation that future cars might be designed with a canopy over the driver's head. This change will of course be contingent upon the agreement of technical regulations. Nevertheless, the idea is that the airflow over the top of the chassis to the rear wing would be more behaved with a canopy; resulting in a chassis design that would be aerodynamically superior to present ones.8 An additional benefit of implementing a canopy would be increased driver safety.
Wing size and shape modifications are also expected to occur. Adjusting these properties will be done with the attempt to increase the efficient use of downforce and to reduce induced drag.
Whatever the future changes may be the design of F1 aerodynamic features is expected to progress without limit. Although they may seem restricted by tight regulations, these regulations only add more challenge to the game that engineers must play. After all, when pushed into a corner, great thinkers devise solutions that override boundaries that had appeared to be present. One must not forget that we are still just scratching the surface on the art of aerodynamics. Do not think that the show is over - there are many magnificent findings yet to be made.
References
. Barnard, R. H. Road Vehicle Aerodynamic Design : England, Henry Ling Limited. 1996.
2. Glenn Research Center. Bernoulli's Equation. http://www.grc.nasa.gov
3. Gray, Will. Taking the Lid Off F1 - Formula One Technical Analysis. http://www.atlas.f1.com/. Kaaizar.Com Incorporated. 2000
4. Gruer, Scott. Streamlining Suspension Members. http://www.gtf1
5. Manishinu, Glenn. Formula One Art and Genius. 2000. http://www.sdwhite.demon.uk/f1/history.htm
6. Marson, AJ. Aerodynamics. http://www.btinternet.com/~AJMarson/aero/Aero.htm
7. Rendall, Ivan. The Power and the Glory - A Century of Motor Racing: London, BBC Books. 1991.
8. Yager, Brian. Aerodynamics In Car Racing. 1999. http://www.nas.nasa.gov
9. http://www.formula1.com/
0. http://www.f1mech.com
1. http://www.mclaren.co.uk
2. http://www.williamsf1.co.uk
3. http://www.formula1.com/news/headlines00/japan/s3516.html