Formula One car
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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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[edit] Engines
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 2.4L V8 formula to prevent the teams from achieving higher rpm and horsepower too quickly. As of the start of the 2006 season most engines on the grid rev up to 19000 rpm, with the Cosworth V8 powering the Williams going up to an astonishing 20000 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 the use of such devices as pneumatic valves, modern F1 engines have revved up to over 18000 rpm since approximately the 2000 season. Almost each year the FIA has enforced material and design restrictions to limit power, otherwise the 3.0L V10 engines would easily have exceeded 22000 rpm and well over 1000hp (750kW). Even with the restrictions the V10s in the 2005 season were reputed to develop 960hp (715kW) . The new 2.4L V8 engines are reported to develop between 720hp and 750hp (535 to 560 kW), with the Cosworth unit being 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) had the option of keeping the current V10 for another season, but with a rev limiter to keep them from having any advantage over the V8 engines.
The engines produce over 100 000 BTU per minute (1750kW) of heat that must be dumped, usually to the atmosphere via radiators and the exhaust, which can reach temperatures over 1000 degrees Celsius (1800 to 2000 degrees Fahrenheit). 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.[citation needed]
All cars have the engine located between the driver and the rear axle. The engines are a stressed member in most cars, meaning that the 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.
As of the 2006 Chinese Grand Prix all development of engines will be frozen until 2009, meaning that the teams will use engines of the same spec for the next two seasons.[1]
The list of Formula One engines gives an overview of engines manufacturers and history of regulation.
- ^ FIA (2006-08-07). The Future of the FIA Formula One World Championship. Press release.
[edit] 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.
[edit] Aerodynamics
The use of aerodynamics to increase the cars' grip was pioneered in Formula One in the late 1960s by Lotus, Ferrari and Brabham. Early designs linked wings directly to the suspension, but several accidents led to rules stating that wings must be fixed rigidly to the chassis. 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 far 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. The front and rear wings are highly sculpted and extremely fine 'tuned', along with the rest of the body such as the turning vanes beneath the nose, bargeboards, sidepods, underbody, and the rear diffuser. They also feature aerodynamic appendages that direct the airflow. Such an extreme level of aerodynamic development means that an F1 car produces much more downforce than any other open-wheel formula; for example the Indycars produce downforce equal to their weight at 190 km/h, while an F1 car achieves the same downforce:weight ratio of 1:1 at 125km/h to 130km/h, and at 190km/h the ratio is roughly 2:1. Therefore, theoretically, F1 cars can drive upside down from 130km/h.
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 low enough to contact the track surface. 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 Circuit de Monaco.
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. New regulations are also being developed to replace the traditional F1 rear wing with two smaller wings over each of the rear wheels. Dubbed the "Centreline Downwash Generating Wing", the smaller wings reduce the turbulent airflow inherent in traditional F1 rear wings and result in a significant increase in a trailing driver's ability to pass a leading car.
[edit] 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 605 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.
[edit] Steering wheel
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. Data such as rpm, laptimes, speed and gear is displayed on an LCD screen. The wheel alone can cost about $40,000, and with carbon fibre construction, weighs in at 1.3 kilograms.
[edit] 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.
[edit] 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 can 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 roadcar tyre has a useful life of up to 80000km, in 2005, a tyre is built to last just one race distance (a little over 300km). 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 - introduced by the Brabham team in 1976 - are used instead of steel or cast iron because of their superior frictional, thermal, and anti-warping properties, as well as significant weight savings. These brakes are designed and manufactured to work in extreme temperatures, up to 1000 C. The driver can control brake force distribution fore and aft to compensate for changes in track conditions. Regulations specify this controll has to be manual, not electronic. An average F1 car can decelerate from 100-0 km/h (62-0 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 Villeneuve (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).
[edit] Performance
Grand Prix cars and the cutting edge technology that constitute them produce an unprecedented combination of outright speed and quickness for the drivers. Every F1 car on the grid is capable of going from nought to 160km/h (100 mph) and back to nought in less than five seconds. During a demonstration at the Silverstone circuit in Britain, an F1 McLaren-Mercedes 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.
As well as being fast in a straight line, F1 cars also have incredible cornering ability. Grand Prix cars can negotiate corners at significantly higher speeds than other racing cars because of the intense levels of grip and downforce. Cornering speed is so high that Formula One drivers have strength training routines just for the neck muscles. Former F1 driver Juan Pablo Montoya claims to be able to perform 300 reps of 50 pounds with his neck.
The combination of light weight (605 kg in race trim), 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 principal 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:
[edit] 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.
[edit] 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 5-6 g when braking from extreme speeds, for instance at the Gilles Villeneuve circuit or at Indianapolis. 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 3.5 seconds.
[edit] 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 (369 km/h in 2004), Indianapolis and Gilles Villeneuve (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 210 km/h already the turning acceleration is 4.0g, as evidenced by the famous esses (turns 3 and 4) at the Suzuka circuit. Higher-speed corners such as Blanchimont (Circuit de Spa-Francorchamps) and Copse (Silverstone Circuit) are taken at above 5.0g, and 6.0g has been recorded at Suzuka's 130-R corner. This contrasts with the 1.3 g of the Enzo Ferrari, 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. A newer and perhaps even more extreme example is the Turn 8 at the Istanbul Park circuit, a 190° relatively tight 4-apex corner, in which the cars maintain speeds between 265 km/h and 285 km/h (in 2006) and experience between 4.5g and 5.5g for 7 seconds - the longest sustained hard cornering in Formula 1 (and hence all motorsport).
[edit] Top Speeds
As of April 2006. the top speeds of Formula 1 cars are a little over 300 km/h at high-downforce tracks such as Albert Park, Australia and Sepang, Malaysia. These speeds are down by some 10 km/h from the 2005 speeds, and 15 km/h from the 2004 speeds, due to the recent performance restrictions (see below). On the low-downforce circuits such as Gilles-Villeneuve (Canada) and Indianapolis (USA), the speeds were 335~350 km/h in 2005, and at Monza (Italy) 365 km/h. However the true top speed in a straight line of a modern Formula 1 car in can be measured when its downforce is modified accordingly for straight-line running. With minimal downforce wing settings, BAR Honda managed to run their FIA race-spec F1 car at 421 km/h on 6 Nov, 2005 during a shakedown leading to their 'Bonneville 400' attempt.
[edit] 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 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% downforce loss.
