7 tricks to keep F1 cars prompt and fuel-efficient
This year the cars in F1 will have engines no thicker than yours, but they’ll still hit incredible speeds. How will they do it?
(Picture: Sutton Photos)
FORMULA ONE motor racing is all about the noise, the fumes, the gas-guzzling cars that would trash the climate in a heartbeat, were we all to drive them. But not any more…
As the two thousand fourteen F1 season kicks off this weekend in Melbourne, Australia, the drivers will race machines with far greater relevance to future road cars. One day their fuel-efficient, energy-recovery technologies will make their way into the cars we drive.
“The F1 cars will have far greater relevance to road cars, with fuel-efficient, energy-recovery tech”
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Until now, the F1 spectacle has been all about the power of the engine. The two thousand thirteen cars, for example, were powered by muscled eight-cylinder, Two.4-litre engines and before that they were even more powerful 10-cylinder, 3-litre animals. This year the engine capacity of F1 cars is ripping off to just 1.6 litres – the same as family cars like the world’s bestselling hatchback, the Ford Concentrate.
The idea is to kit out the cars with a puny engine of a “road-car relevant” size accomplish with a clutch of energy recovery technics. Along with better aerodynamics, these will ensure the engine has both green credentials and the speed the spectacle requests. Jenson Button, former F1 world champ with the Brawn GP team, who now drives for McLaren, is amazed. “The power of the engine is nice. It’s very torquey,” he told Fresh Scientist, referring to the fresh car’s acceleration.
So why the switch? Major carmakers like Ford, Honda, Toyota and BMW have dropped out of F1 competition in latest years and Volkswagen-owned Audi has declined to join because they argue that F1 is irrelevant to improving road cars. So F1’s governing bod, the FIA, and the sport’s three engine-makers – Renault, Ferrari and Mercedes – have worked out how to realign F1’s rules with the greener aims of mainstream carmakers. They hope that will attract more of the mainstream to F1.
The purpose is to maximise fuel efficiency. “The automotive industry is focused on fuel consumption and the CO2 emissions it generates. So F1 has turned the rules on their head to align with that,” says Andy Cowell, managing director of Mercedes AMG High Spectacle Powertrains in Brixworth, UK, which develops F1 engines. “The fundamental challenge now is to convert as much of the chemical energy in the fuel into mechanical energy as efficiently as possible.”
FIA’s fresh rules are raunchy: the fresh F1 engine has to be at least thirty per cent more fuel-efficient than last year’s engines. If they are not, some of F1’s multimillionaire drivers risk crimson faces by not ending the race. That’s because fuel efficiency is now being enforced by two mechanisms: a maximum fuel flow rate of one hundred kilograms per hour, which caps the engine power, and a total race fuel allowance of just one hundred kilograms, compared with last season’s one hundred fifty kilograms.
This means teams have to finish the 305-kilometre race on two-thirds of last season’s fuel allowance. But to keep the spectators blessed, they must do so at the same speeds.
To make this possible the 1.6-litre engine needs to play a few tricks to recover energy that normally goes to waste. Providing a hint of just how sophisticated the fresh engine is, Mercedes says on its website: “The engine is no more. Long live the power unit”.
The heart of the two thousand fourteen power unit is the freshly shrunk engine that has also had its maximum rotational speed cut from Eighteen,000 revolutions per minute to a more efficient 15,000 rpm. Then a raft of energy-recovery mechanisms come in to play (see diagram, below).
Since 2009, F1 cars have used a regenerative braking system, like that used in hybrid cars, to charge the car’s 25-kilogram, lithium ion battery. Once a lap the battery can discharge into a motor, providing a 7-second kinetic energy boost to the car’s drive shaft. This Kinetic Energy Recovery System (KERS) comprised a combined motor and generator, but this has now been upgraded and is known as the motor-generator unit-kinetic. In generator mode, the MGU-K can now harvest up to five times as much braking energy as the KERS, at two megajoules per lap. As a motor, it can take four megajoules of energy from the battery and send it to the engine, equating to an extra one hundred sixty one horsepower (120 kilowatts) over thirty seconds.
The next energy-recovery trick is a novel take on a turbocharger, something that has been used in F1 before but which comes with an extra trick up its sleeve this year. In a standard turbocharger a turbine sits in the hot harass gas stream and turns a compressor on the air intake side of the engine. This boosts the power of the engine by pumping higher pressure air into the firing cylinders.
In the fresh turbocharger, nothing gets wasted. Once the harass gas pressure thrusts the compressor in the air intake to 100,000 rpm any extra energy from the turbocharger’s turbine is harvested to turn a device, called the motor-generator unit-heat, or MGU-H. This can charge the car’s battery still more or dump energy into the MGU-K to send to the drivetrain to give the driver an extra boost. This means it uses less fuel for more power.
All of this, in pre-season testing in Spain and Bahrain at least, seems to supply the necessary efficiency gains. “We are producing over thirty per cent more power for every unit of fuel consumed compared with last year’s V8 engine,” says Cowell.
“We are producing over thirty per cent more power for every unit of fuel consumed”
These switches should make life lighter for the drivers too as they do not have to think about activating the kinetic and fever recovery systems – jointly known as the Energy Recovery System (ERS) – as they did with KERS in previous years. Clever electronics make sure it is all available through the throttle: if the energy is available from the engine or the battery they can have it on request. Similarly, harvesting braking energy to charge the battery is now automatic, too.
The identical electronic control units in F1 cars are made under FIA rules by McLaren Applied Technologies (MAT) of Woking, UK – a company kept rigorously separate from the rock hard’s McLaren F1 racing team, for the sake of fairness. The control units choreograph everything from throttle control down to switching the gears. Their software has been entirely rewritten for the fresh energy-recovering turbos, says MAT vice-president Peter van Manen.
“In terms of road relevance, the entire concept of recovering energy from the harass is very titillating because half the energy of a road car is lost as fever through the tailpipe,” Van Manen says. “Being able to recover some of that could have a big influence on carbon emissions and fuel economy.”
The true test will be the reliability of the elaborate turbo engines with all their electrified add-ons – and the reaction of the F1 fans to the engine sound, beginning at the Albert Park Lake Grand Prix Circuit in Melbourne, this weekend. Some diehard fans may be disappointed. “It’s certainly quieter and more melodic,” says one F1 team member who observed trials in Jerez, Spain.
Ahead of the race, things were looking good for the driving practice: “Coming out of the corners you have so much torque it’s titillating,” says Button. “I think the positive thing is we have the ERS unit to pack in the gaps. I would say it’s a very drivable engine at this early stage.”
This article appeared in print under the headline “A mean green machine”
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