CFD simulation at Williams

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Life in the fluid lane

The opening race of a Formula One season is the first real time that fans can gauge the true performance of the teams, drivers and cars. New partnerships are put to the test and the equipment and technology that is often refined right up to Friday qualifying is sent out on track to deliver results.

The title challenging BMW WilliamsF1 Team and their revolutionary WilliamsF1 BMW FW26 car represents the culmination of months of development and testing work - at WilliamsF1 headquarters in Grove, England, BMW headquarters in Munich, Germany and numerous test circuits throughout Europe.

Juan Pablo Montoya drives an FW26
But it all began in a department in the WilliamsF1 building. Here a team of designers, developers and aerodynamicists were charged by Patrick Head, Technical Director of WilliamsF1, to create a step change in the design philosophy of the Team. And that meant going back to the "virtual" drawing board.

Breaking the racing code

At the heart of the design and aerodynamics department at WilliamsF1 headquarters lies a titan of technological power. From the same stable as the computer that broke the human DNA code comes the eight-node HP AlphaServerâ„¢ HP320, a supercomputer with the facility for breathtaking calculations and computing far beyond the reach of human ability.

The HP AlphaServer at WilliamsF1 is the largest single-cluster automotive supercomputer in the UK and with it the team gains a vital edge over their competition, in the ability to simulate air flow over a whole car in a single test and to model the behaviour of the car under conditions other than steady-state airflow.

Andrew Collis, HP Director of corporate sponsorships and Global F1 said, "The efficiency gains combined with increased processing power means the team can run more complex simulations, ensuring detailed analysis of the 3000+ parts which comprise F1 cars."

Other teams have the ability to test the aerodynamic performance of a "virtual car" but, through restrictions in computing capacity, they have to test components of the car in isolation - the front wing and barge boards in one test, the rear wing in another. Only the BMW WilliamsF1 Team can test the whole car as a single unit.

Virtual racing. Tangible results

The primary application of the Alpha supercomputer's success is in Computational Fluid Dynamics (CFD). CFD concerns the analysis of an object, in this case the FW26 car, within a computer simulation, using basic laws of physics governing air flow. In CFD tests, the team can determine the aerodynamic efficiency of the car and make relevant changes to the design within the computer environment.

CFD technology has become progressively more important to the efficiency of Formula One car design and the relative success of the teams. It is an intensely processor and memory hungry application. Each virtual air molecule acts in a different way, depending on the variables of the wind, the ground and the different surfaces of the car it hits. Multiply this by the thousands of separate particles that hit the car as it travels along and you are soon faced with lots of calculation requirements.

A race car is one of the most difficult environments to conduct CFD tests in, with the down near fixed ground surface, the rotating wheels and the rather messy aerodynamic geometry of a Formula One car," explains Patrick Head, Technical Director at WilliamsF1. "But it is a very advancing science and it is a very important and vital tool for each of the top Formula One teams."

Less time speculating. More time perfecting

A sizeable proportion of an F1 team's yearly budget is invested in the design and development programme that goes into creating a racing package for that season. HP's AlphaServer effectively takes on the role of virtual wind tunnel, allowing the team to test aerodynamic elements of the car without having to build a single component.

The new FW26 chassis was born from the analysis of exhaustive simulations, which could be performed in an hour, rather than the fifteen hours it previously took. The efficiency gains mean that engineers can spend more time testing and perfecting the car on-screen and not in the costly wind tunnel.

"We make full use of HP's breadth and depth of technological know-how," said Neil Davis, IT Development Manager at WilliamsF1. "Whatever we need in the way of IT expertise, HP can put at our disposal."

HP Formula One
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