Adapting to Formula 1 engine restrictions

Materials World magazine
,
1 Jun 2008

In an industry that has long enjoyed a reputation of leading technological and engine development, Formula 1 (F1) engine designers had to go back to the drawing board after the Fédération Internationale de l’Automobile (FIA) 2006 regulations were published.

Issues involving extreme cost spending and the ‘unfair advantage’ wealthier teams like Ferrari had over their poorer competitors led the FIA to instigate an engine homologation requirement in 2006, as well as a five-year engine development freeze starting in 2008.

The bigger V10 engine used prior to 2006 was scrapped for a smaller, four-stroke V8 engine. A minimum weight rule of 95kg was implemented – a regulation car designers did not have to deal with before (competitive engines had previously been around 90kg).

Engines also have to last two races, not just one, and a list of costly ‘exotic’ materials are banned from use, including magnesium-based alloys, metal matrix composites, intermetallic materials, and alloys containing more then five per cent by weight of beryllium, iridium or rhenium.

For Toyota Motorsport, based in Cologne, Germany, these restrictions posed some challenges. ‘Our V10 [engine] was already lower than the minimum weight for the V8,’ says Luca Marmorini, Senior General Manager – Engine. ‘So when we removed two cylinders from the V10, we could have had an engine 10kg lighter than the minimum weight.’

Much of this lightness was due to Toyota’s use of magnesium. ‘We invested a lot in the past to bring magnesium parts into the engine. The thin wall castings were also in magnesium,’ says Marmorini. His team has had to increase the thicknesses of engine parts and switch to ‘more robust’ materials to create a heavier, longer-lasting engine.

According to the 2006 FIA rules, pistons must be manufactured from an aluminium alloy, connecting rods from iron or titanium-based alloys, crankshafts and camshafts from an iron-based alloy, and valves from alloys based on iron, nickel, cobalt or titanium. Reciprocating and rotating components cannot be manufactured from a graphitic matrix, metal matrix composites or ceramic materials.

‘It is a pity that we are frozen in materials development,’ Marmorini adds, ‘because I think there are a lot of interesting materials where F1 could act as a leader in application, and this could have been extended to normal cars’.

However, others take a more pragmatic view. ‘The things that were excluded were in development or used in marginal applications,’ says Rob White, Team Deputy Managing Director for Renault F1, based in Enstone, UK. ‘There’s still plenty of challenging stuff to do, and the definition of conventional technologies in the rules does not exclude careful exploitation of conventional alloys.’

Energy recovery

While engine and materials work has ground to a halt, motor designers are not twiddling their fingers. The 2008 season has seen standardisation of electronic control units. This requires alterations in order to work with existing engines. Furthermore, in 2009, kinetic energy recovery systems (KERS) will be introduced to reduce fuel usage.

The KERS, which captures a car’s kinetic energy while it is breaking and releases it under acceleration, is permitted to recover energy at a maximum rate of 60kW.
Using KERS could allow F1 ‘to become a shop-window for a new piece of technology that people can see improves the fuel efficiency of a vehicle, and which might be coming their way soon,’ says Brian O’Rourke, Chief Composites Engineer at Williams F1, based in Wantage, UK. ‘Traditionally, manufacturers raced cars to “improve the breed”, so it would be getting back to that.’

Williams F1 is investing in mechanical flywheel technology, whereby a flywheel rotating up to 100,000rpm would capture kinetic energy for later release. Most manufacturers are still looking at a variety of recovery devices, says Marmorini, including flywheel, capacitor or battery systems.

The difficulties associated with this technology, however, are many, he adds. ‘You have to introduce a technology that is not yet fully developed into a F1 car. Depending on the storage device you go with, it could be a big component [at least 20kg], and locating it in a car is a challenge if you want to design a fast car’.
Motor engine teams will also be busy maintaining their longer-lasting machines through regular testing and ensuring the quality of parts, while keeping an anxious eye out for new rules in 2010.

 

Further information:

Federation Internationale de L'Automobile

Toyota Motorsport

Renault F1