F1 2021 design goals put to the test in the wind tunnel

Formula 1 has released images of the wind tunnel testing it has been carrying out with a 2021 car model in order to check its aerodynamic impact.

The sport wants to introduce significant regulation changes in 2021, designed to make it easier for a following car to stay close to the car ahead. Currently, cars lose as much as 50% of their downforce when in the wake of another car, but F1 and the FIA are working together in an attempt to reduce that to around 5%, and have been testing their solutions in the Sauber wind tunnel in Switzerland.

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“The wind tunnel testing we are doing is slightly different to what the teams might do,” F1’s Chief Technical Officer Pat Symonds told the official F1 website. “The teams concentrate solely on the forces on the car, through a variety of attitudes as they move the car around. While we naturally have an interest in what those forces are and particularly how those forces change as the car moves, we’re even more interested in what is happening to the turbulent air behind the car.

“For that reason, although we are doing most of our development in CFD -- and that CFD is using some pretty advanced techniques which aren’t commonly used by the teams -- we want to back up the virtual simulations with a physical simulation. We also chose to use a 50% model rather than a 60% model and we chose to run that model quite a long way forward in the wind tunnel, so this gave us the opportunity to best inspect the wake of the car.”

The Sauber wind tunnel was chosen due to its automatic rake system that is used to measure the wake behind the car, and the latest test took place ahead of the German Grand Prix using Sauber’s independent consultancy group to ensure no advantage could be gained by the Alfa Romeo team.

After a 60% scale model of a 2018 car was tested in January and then a version of the 2021 car with current-spec wheels ran in the tunnel in March, a 50% scale model featuring 18-inch wheels was used for the latest test, which Symonds says provided more opportunity to focus on the car’s wake.

Physical modeling aims to confirm the improved aero numbers found via CFD.

“It takes up less room in the tunnel and therefore it allows us to look, in terms of car lengths, further behind,” says Symonds. “If you imagine you have a full-size car in there, you could only look at a tenth of a car when it is behind, so 50% is a good compromise in that we can still get a good level of detail on the model but we still have distance behind.

“It’s true teams have tended to go more to 60% these days. There are advantages to that, in modeling, but modern manufacturing techniques, particularly additive manufacturing and stuff like that, allows you to make very accurate 50% models these days.”