01 Nov 2006
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‘Smoothed Particle Hydrodynamics’ shows how fuel moves
McLaren Mercedes use this for their Formula 1 racing car as it changes speed and direction
A new way of modelling how fuel moves in cars during high speed manoeuvres has helped to boost the performance of the Team McLaren Mercedes racing car. Using a computer simulation based on the movement of particles, the ATC has enabled the Formula 1 team to rethink its fuel system design and edge forward in the battle for domination of the grid.
Originally designed for predicting sloshing in aircraft fuel tanks, the ATC has been using its ‘smooth particle hydrodynamics’ model to show how fuel moves around in a Formula 1 racing car as it changes speed and direction. Up to now there has been no way of visualising accurately the way that fuel behaves especially when the tank is nearly empty. This knowledge is vital to judge the best time for a driver to make a pit stop to refuel. In a sport where improvement of hundredths of a second per lap is enough to make a difference, timing is everything. The computer model simulates fluids as a collection of individual particles that can interact in a realistic manner. What makes the ATC model special is that it can predict where the surface of a liquid will fall under a wide range of condition.
“Smooth particle hydrodynamics is perfect for visualising where the free surface of the fuel is” says Robert Banim, project leader at the ATC. “It’s impossible to do this with other computational fluid dynamics models and it allows fuel tank designers to judge where best to put take-off pipes to make sure every last drop of fuel can be used” he says.
Formula 1 cars have staggering accelerations of 5g and over (equivalent to jet fighters) and when cornering the fuel can end up virtually anywhere in the tank. The ATC modellers took recordings of all the accelerations during a series of track events and combined this with a computer model of the Team McLaren Mercedes tank.
The work of Robert and his team has enabled a redesign of Team McLaren Mercedes’ fuel tanks, leading to more accurate determination of the fuel remaining and improvements to the car’s centre of gravity. These advances have already enhanced track performance as the redesigned fuel tank was used on the Team McLaren Mercedes 2005 car – the MP4-20, widely regarded within the sport as the fastest on the grid throughout the season.
A similar technique is now being used to assist the design of the gearbox by modelling the movement of oil through the connecting pipes, the gearbox enclosure and the rotating gears.
This test programme started in January 2005 with the results fed into the design of the 2006 car.
