May 18, 2011
Car-Addicts.com presents you the technology behind a wind tunnel and aerodynamic importance of this tool in developing a formula one car.
In the romantic era of Formula 1, teams predominantly developed race cars by testing them on the circuit before the race itself, but progress has inevitably made its mark on the biggest motorsport competition.
Top teams have begun to increasingly rely more on technology to build competitive race cars, and in recent decades the use of facilities such as wind tunnel or computerized technology CFD (Computation Fluid Dynamics) has become a necessity for survival. In addition, banning tests during season since 2009 as a cost reduction left the teams with only two viable options for development of race cars: wind tunnel and CFD.
Will present the main characteristics of a wind tunnel and its importance in building and developing competitive formula one cars.
What is a wind tunnel
Under natural conditions, a formula one car moving faces a resistance force from the air and through the wind tunnel engineers have reversed the process: the monopost stands still, while the air is directed over. The effect is basically the same with the difference that engineers can more accurately assess the influence of air on the car’s performance.
Currently, there are many types of wind tunnels, depending on how they are classified: according to the architecture we are talking about wind tunnels with open circuit or closed circuit; depending on the speed they are subsonic, transonic, supersonic or hypersonic; after air pressure they are atmospheric or with variable density; by size we talk about scale models or in natural size. According to FIA regulations, teams can use models to scale up to 60% and the maximum air speed can’t exceed 50 meters per second.
Construction of a wind tunnel
As the name suggests, a wind tunnel is primarily a tunnel with a variable length, reaching 140-150 meters for most teams from Formula 1. Also, the tunnel’s diameter is generally about 10 meters (9,4 meters in case of the wind tunnel used by Sauber) and for the construction is used about 400 tons of steel with a thickness of 8-10 mm.
To generate “wind” are used one or more large fans. For example, McLaren uses a single ventilator with a huge four-meter diameter rotating at a speed of 600 revolutions per minute.
In addition to these tools teams are using supercomputers to obtain data, whose capacity is impressive. The performance of such a supercomputer, consisting in fact from several interconnected computer, reaching 2,3 Tflops per second, 1 TB of RAM and a storage capacity of 11 TB.
Wind tunnel – how does it work
Operating modul of a wind tunnel is not nearly as simple as it seems at first sight, primarily because of turbulence. Basically, when air flows through the tunnel, it passes first through a series of processes that ensure its uniformity before reaching the testing monopost, so that engineers have data obtained with higher accuracy. First, the air is slowed by introducing it to a wider section of the tunnel, and then enters into a area where some of turbulence are eliminated using a “net”.
Afterwards, the air is forced through a “honeycomb” to be stronger, and two more “nets” eliminate its latest turbulence. From this point, air passes into a contraction chamber which increases its speed before entering the testing cell under optimum conditions.
The wind tunnel is used primarily for evaluation of new components, such as a front wing, but the advantages of this tool doesn’t stops there. Wind tunnel can be successfully used to estimate performance for changing angle of incidence of a wing, with the settings used by the pilot, for the cooling system or brake system, depending on the nature of the circuit on which the team will compete. Thus, these data create a map showing the force of aerodynamic downforce and the force of air resistance for each circuit.
Video - Here’s how Lotus evaluated in the Aerolab wind tunnel, the first monopost with which they compete in Formula 1 2010 season:
Wind tunnels used by F1 teams
Most teams are using their own wind tunnels, but there are exceptions, even among the top teams:
* Ferrari: Maranello, Italy and the the wind tunnel at Koln owned by Toyota Motorsport;
* McLaren: McLaren Technology Centre, Woking, United Kingdom;
* Red Bull Racing: Milton Keynes, United Kingdom;
* Toro Rosso: Milton Keynes, United Kingdom;
* Renault: Enstrone, United Kingdom;
* Williams: Oxfordshire, United Kingdom;
* Mercedes GP: Brackley, United Kingdom;
* Force India: Aerolab;
* Sauber: Hinwill, Switzerland;
* Hispania Racing: Brackley, United Kingdom (rented from Mercedes GP);
* Virgin Cosworth: is not using a wind tunnel to the develop its formula one cars.