Formula One cars
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Modern Formula One cars are single-seat, open cockpit, open wheel race cars that have substantial wings at front and rear, and position the engine behind the driver. The regulations governing the cars are unique to the championship. The current Formula One regulations specify that cars must be constructed by the racing teams themselves.
See Formula One regulations for a summary of the current technical and sporting regulations.
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Engines
Image:F1 BAR Honda 006.jpg For a decade F1 cars have run with 3.0 litre normally-aspirated V10 engines, but In an attempt to slow the cars down, the FIA has mandated that as of the 2006 season there will be a new engine package. The regulations specify that the cars must be powered by 2.4 litre naturally-aspirated engines in the V8 configuration that have no more than four valves per cylinder. Further technical restrictions such as a ban on variable intake trumpets have been also been introduced with the new 2.4 L V8 formula to prevent the teams from achieving higher rpm and horsepower too quickly. As of the start of the 2006 season most engine on the grid rev up to 19,000 rpm, with the Cosworth V8 on the Williams going up to an astonishing 20,000 rpm in qualifying trim.
Once the teams started using exotic alloys such as titanium in the late 1990s, the FIA banned the use of exotic materials in engine construction, and only aluminum and iron alloys were allowed for the pistons, cylinders, connecting rods, and crankshafts. Nevertheless through engineering on the limit and use such devices as pneumatic valves, modern F1 engines have revved up to over 18,000 rpm since approximately the 2000 season. Almost each year the FIA has enforced material and design restrictions to limit power, otherwise the 3.0 L V10 engines would easily have exceeded 22,000 rpm and well over 1000 hp (750 kW). Even with the restrictions the V10's in the 2005 season were reputed to develop 960 hp (715 kW) . The new 2.4 L V8 engines are reported to develop between 720 and 750 hp (535 to 560 kW), with the Williams' Cosworth unit the most powerful.
The more poorly funded teams (Ferrari spends hundreds of millions of dollars a year developing their car, while the former Minardi team spent less than 50 million) will have the option of keeping the current V-10 for another season, but the engines will have their components de-tuned to keep them from having any advantage over the V-8 engines.
The engines produce over 100,000 BTU per minute (1,750 kW) of heat that must be dumped, usually to the atmosphere via radiators and the exhaust, which can reach an 1,800 to 2,000 degrees Fahrenheit (1000 degrees Celsius). They consume around 650 litres (23 ft³) of air per second. Race fuel consumption rate is normally around 75 litres per 100 kilometres travelled (3.1 US mpg). Nonetheless a Formula One engine is over 20% more efficient at turning fuel into power than even the most economical small car.
All cars have the engine located between the driver and the rear wheels. The engines are a stressed member in most cars. This means that engine is part of the structural support framework, being bolted to the cockpit at the front end, and transmission and rear suspension at the back end.
In the 2004 championship, engines were required to last a full race weekend; in the 2005 championship, they are required to last two full race weekends and if a team changes an engine between the two races, they incur a penalty of 10 grid positions.
The list of Formula One engines gives an overview of engines manufacturers and history of regulation.
Transmission
Formula One cars use semi-automatic sequential gearboxes with six or seven forward gears and one reverse gear. The driver signals gear changes using paddles mounted on the back of the steering wheel and electro-hydraulics perform the actual change as well as throttle control. Clutch control is also performed electro-hydraulically except from and to a standstill when the driver must operate the clutch using a lever mounted on the back of the steering wheel. By regulation the cars use rear wheel drive. A modern F1 clutch is a multi-plate carbon design with a diameter of less than four inches (100 mm), weighing less than a kilogram and handling 900 horsepower (670 kW) or so.
Aerodynamics
Image:Rear wing f1 n.jpg The cars' aerodynamics are designed to provide maximum downforce with a minimum of drag; every part of the bodywork is designed with this aim in mind. Like most open wheeler cars they feature large front and rear aerofoils, but they are more developed than American open wheel racers, which depend more on suspension tuning; for instance, the nose is raised above the centre of the front aerofoil, allowing its entire width to provide downforce. They also feature aerodynamic appendages that direct the airflow.
F1 regulations prohibit the use of ground effects, so to minimise the downforce provided by ground effects the undertray is flat between the axles and a wooden "plank", measured before and after a race, runs down the middle of the car to prevent the cars from running so low to the ground that they scrape against it. However, a substantial amount of downforce is provided by using a rear diffuser which rises from the undertray at the rear axle to the actual rear of the bodywork. This downforce comes at the cost of what is actually a quite high aerodynamic drag coefficient (about 1 according to Minardi's technical director Gabriele Tredozi [1]), so that, despite the enormous power output of the engines, the top speed of these cars is less than that of World War II vintage Mercedes Benz Silver Arrows racers; however this is more than compensated for by the ability to corner at huge velocity. The aerodynamics are adjusted for each track; with a relatively low drag configuration for tracks where high speed is relatively more important like Autodromo Nazionale Monza, and a high traction configuration for tracks where cornering is more important, like the Österreichring.
The FIA is hoping to rid F1 of small winglets and other parts of the car (minus the front and rear wing) used to manipulate the airflow of the car. This is in order to not only decrease downforce, but also to increase drag. As it is now, the front wing is shaped specifically to push air towards all the winglets and bargeboards so that the airflow is smooth. Should these be removed, various parts of the car will cause great drag when the front wing is unable to shape the air past the body of the car. There will also be modifications to the rules on rear wings so as to prevent severe disturbances in the air as cars try to pass one another on curves. The overall goal is to increase overtaking by decreasing downforce.
Formula one cars produce such a phenomenal downforce that theoretically they could drive upside down on a ceiling, this is because the downforce is higher than the force of the weight acting down.
Construction
The cars are constructed from composites of carbon fibre and similar ultra-lightweight (and incredibly expensive to manufacture) materials. The minimum weight permissible is 600 kg including the driver, fluids and on-board cameras. However, all F1 cars weigh significantly less than this (some as little as 440 kg) so teams add ballast to the cars to bring them up to the minimum legal weight. The advantage of using ballast is that it can be placed anywhere in the car to provide ideal weight distribution.
Steering wheel
Image:2004FerrariWheel.jpg The driver has the ability to fine tune many elements of the race car from within the machine using the steering wheel. The wheel can be used to alter traction control settings, change gears, apply rev limiter, adjust fuel air mix, change brake pressure and call the radio. Telemetry data such as rpm, laptimes, speed and gear are displayed on an LCD screen. The wheel alone can cost about $40,000, and with carbon fibre construction, weighs in at 1.3 kilograms.
Fuel
The fuel used in F1 cars is fairly similar to ordinary gasoline, albeit with a far more tightly controlled mix. Formula One fuel cannot contain compounds that are not found in commercial gasoline, in contrast to alcohol-based fuels used in American open-wheel racing. Blends are tuned for maximum performance in given weather conditions or different circuits. During the period when teams were limited to a specific volume of fuel during a race, exotic high-density fuel blends were used which were actually heavier than water, since the energy content of a fuel depends on its mass density.
To make sure that the teams and fuel suppliers aren't violating the fuel regulations, the FIA requires Elf, Shell, and the other fuel teams to submit a sample of the fuel they are providing for a race. At any time, FIA inspectors can request a sample from the fueling rig to compare the "fingerprint" of what is in the car during the race with what was submitted. The teams usually abide by this rule, but in 1997, Mika Häkkinen was stripped of his third place finish at Spa-Francorchamps in Belgium after the FIA determined that his fuel was not the correct formula.
Tyres and brakes
By regulation, the tyres feature a minimum of four grooves in them, with the intention of slowing the cars down (a slick tyre, with no indentations, is best in dry conditions). They must be no wider than 355 mm and 380 mm at the front and rear respectively. Unlike the fuel, the tyres bear only a superficial resemblance to a normal road tyre. Whereas a normal car tyre has a useful life of up to 80,000 km, and even motorcycle tyres are normally good for 15,000 km, in 2005, a tyre is built to last just one race distance, which is a little over 300 km. This is the result of a drive to maximize the road-holding ability, leading to the use of very soft compounds (to ensure that the tyre surface conforms to the road surface as closely as possible).
Disc brakes consist of a rotor and caliper at each wheel. Expensive carbon-carbon composite rotors are used instead of steel or cast iron because of their superior frictional, thermal, and anti-warping properties, as well as significant weight savings. The driver can control brake force distribution fore and aft using a control on the steering wheel to compensate for changes in track conditions. An average F1 car can decelerate from 100-0 km/h (60-0 mph) in about 17 metres (55 feet), compared with a Dodge Viper (considered one of the best mass-production street cars for braking), which takes around 34 metres (112 feet). Usual braking forces for an F1 car are 4.5 g to 5.0 g (45 to 50 m/s²) when braking from 300 km/h, and can be as high as 5.5 g at the high-speed circuits such as Gilles Villenueve (Canadian GP) and Monza (Italian GP). This contrasts with 1.0 g to 1.5 g for the best sports cars (the Bugatti Veyron is claimed to be able to brake at 1.3 g).
Performance
F1 cars and the cutting edge technology that constitute them produce an unprecedented combination of outright speed and quickness for the drivers, or pilots. Every F1 car on the grid is capable of going from 0 to 160 km/h (100 mph) and back to 0 km/h in less than five seconds. During a demonstration at the Silverstone circuit in Britain, a McLaren F1 car driven by David Coulthard gave a pair of Mercedes-Benz street cars a head start of seventy seconds, and was able to beat the cars to the finish line from a standing start.
Despite F1 cars being fast, they also have incredible turning ability. F1 cars can take corners at much higher speeds then a normal racing car because of the intense levels of grip and downforce. The upside-down wings keep the car racing on the ground on corners at speeds where normal cars would flip over and crash. In fact, the downforce at high speeds is greater than the gravitational force, in principle allowing an F1 car to be driven upside down.
The combination of extreme light weight (440 kg dry), power (950 bhp with the 3.0 L V10, 750 bhp with the 2006 regulation 2.4 L V8), aerodynamics, and ultra-high performance tyres is what gives the F1 car its performance figures. The principle consideration for F1 designers is acceleration, and not simply top speed. Acceleration is not just linear forward acceleration, but three types of acceleration can be considered for an F1 car's, and all cars' in general, performance:
- Linear forward acceleration
- Linear deceleration (braking)
- Turning acceleration (centripetal acceleration)
Unless a car is to be raced solely on high-speed ovals (where only top speed matters), all three accelerations should be maximised. The way these three accelerations are obtained and their values are:
Forward acceleration
The 2006 F1 cars have a power-to-weight ratio of 1250 hp/tonne (930 W/kg). Theoretically this would allow the car to reach 100 km/h in less than 1 second. However the massive power cannot be converted to motion at low speeds due to traction loss, and the usual figure is 2 seconds to reach 100 km/h. After about 130 km/h traction loss is minimal due to the combined effect of the car moving faster and the downforce, hence the car continues accelerating at a very high rate. The figures are (for the 2005 Renault R25):
- 0 to 100 km/h: 1.9 seconds
- 0 to 200 km/h: 3.9 seconds
- 0 to 300 km/h: 8.4 seconds, may be slightly more or less depending on the aerodynamic setup.
The acceleration figure is usually 1.4 g (14 m/s²) up to 200 km/h, which means the driver is pushed back in the seat with 1.4 times his bodyweight.
Deceleration
The carbon brakes in combination with the aerodynamics produces truly remarkable braking forces. The deceleration force under braking is usually 4 g (40 m/s²), and can be as high as 5 g when braking from extreme speeds, for instance at the Gilles Villenueve circuit. Here the aerodynamic drag actually helps, and can contribute as much as 1.0 g of braking force, which is the equivalent of the brakes on most sports cars. In other words, if the throttle is let go, the F1 car will slow down under drag at the same rate as most sports cars do with braking, at least at speeds above 150 km/h. The drivers also utilise 'engine braking' by downshifting rapidly.
As a result of these high braking forces, an F1 car can come to a complete stop from 300 km/h in less than 3 seconds.
Turning acceleration
As mentioned above, the car can accelerate to 300 km/h very quickly, however the top speeds are not much higher than 330 km/h at most circuits, being highest at Monza (365 km/h in 2004), Indianapolis and Gilles-Villenueve (about 350 km/h at both). This is because the top speeds are sacrificed for the turning speeds. An F1 car is designed principally for high-speed cornering, thus the aerodynamic elements can produce as much as three times the car's weight in downforce, at the expense of drag. In fact, at a speed of just 130 km/h, the downforce equals the weight of the car. As the speed of the car rises, the downforce increases. The turning force at low speeds (below 70 to about 100 km/h) mostly comes from the so-called 'mechanical grip' of the tyres themselves. At such low speeds the car can turn at 2.0 g. At 200 km/h already the turning acceleration is 4.0 g, as evidenced by the famous Turn 8 at the Istanbul Park circuit. This contrasts with the 1.3 g of the Ferrari Enzo, one of the best racing sports cars.
These turning accelerative forces allow an F1 car to corner at amazing speeds, seeming to defy the laws of physics. As an example of the extreme cornering speeds, the Blanchimont and Eau Rouge corners at Spa-Francorchamps are taken flat-out at above 300 km/h, whereas the race-spec GT cars in the ETCC can only do so at 150–160 km/h.
Recent FIA performance restrictions
In an effort to reduce speeds and increase driver safety, the FIA has continuously introduced new rules for F1 constructors in the 1990s. These rules have included restrictions on engine computer technology, as well as the introduction of grooved tyres. Yet despite these changes, constructors continue to extract performance gains by increasing power and aerodynamic efficiency. As a result, the pole position speed at many circuits in comparable weather conditions has dropped between 1.5 and 3 seconds in 2004 over the prior year's times. In 2006 the engine power was reduced from 950 bhp to 750 bhp (710 to 560 kW) by going from the 3.0 L V10's used for over a decade to 2.4 L V8's. This is carried over into 2006 the aerodynamic restrictions introduced in 2005 meant to reduce downforce by about 30%. However most teams were able to successfully reduce this to a mere 5 to 10%.