Allianz F1 Safety Focus - CFD

When building a Formula 1 car, the engineers concentrate primarily on aerodynamic efficiency. Good aerodynamics is the most important performance criterion in Formula 1: it is the easiest way for a team to gain an advantage over its rivals. CFD is an invaluable help in the search for the best compromise between as much downforce as possible and as little air resistance as possible. The HP computer makes the airflows surrounding the vehicle visible, and at the same time shows the effects of individual vehicle parts on each other and on the aerodynamics. This representation therefore also shows the engineers where they are generating, and where they are losing, downforce. And, if they wish, they can immediately adapt their virtual model on the computer according to their new findings.

In many cases, there is a lack of time for extensive testing of new parts because of the high development pressure in Formula 1. That is why realistic and meaningful computer simulations are an invaluable help for the engineers. Even at an early stage in the development, they set the course for the cars' good performance on the race track. Even so, these simulations are only possible with the help of enormous quantities of data. The WilliamsF1 engineers are able to call on an HP super-computer similar to the one that scientists used to decode human DNA. The

following figures show just how much they exploit this unique possibility: in the 2001 season, a data volume of 250 gigabytes flowed at WilliamsF1 during the development of the race car; in 2002, that increased to 800; and in 2003 the figure reached an almost inconceivable 4,000 gigabytes.

Through using CFD, WilliamsF1 has a major advantage over its rivals: while all the other teams can only test individual parts separately from each other, but not the entire vehicle, the capacity of the supercomputer allows the WilliamsF1 engineers to simulate all of the airflows acting on the vehicle at the same time. This turns the computer into a sort of virtual wind tunnel, because it means that aerodynamic elements can be tested even before they are actually produced.

Thanks to the constantly increasing power of the supercomputers, the engineers' work with CFD is also becoming more and more realistic in series production. The programs have long since been used for optimising all the important flow processes, and not just in the field of aerodynamics.

"We simulate the throughput and the deposit behaviour in soot filters and also the fuel flow in the injection process," said Dr Christoph Lauterwasser from the Allianz Centre for Technology. "So the CFD methodology contributes to the efficient use of the fuels and the reduction of pollutant emissions."

In spite of the triumphant march of CFD into Formula 1 design offices, the real wind tunnels are certainly not becoming superfluous. On the contrary, the systems complement each other beautifully. The wind tunnel is still absolutely indispensable, even just for checking the computer simulations for their viability in everyday use. It is only with the tunnel's technical possibilities that the engineers can simulate various racing situations at the touch of a button, such as driving over kerbs or hard braking, for instance. A task that would take 30 minutes in the wind tunnel would often take hours on the computer, because of the enormous data volumes involved. So each of the systems has its own strengths.

"In the wind tunnel, you can find out how something works," explained Naethan Eagles, "but not why it works better. Only the computer can show you that."