The front wing of a Formula One car creates about 25% of the total cars downforce. Although this only occurs in ideal circumstances. When a preceding car runs less than 20m in front.
The basic principle of a formula one wing is exactly the same as with a common aircraft. The greatest difference is the direction air is pressed and how that aerodynamic force acts on the vehicle.
Renault engineer Pat Symonds gives an insight in the particular properties of the Imola Formula One circuit.
Wind tunnels in general are used for testing purposes and aerodynamical optimization. They are specially designed to simulate airflow like in open air and flow velocity as close as possible to the situation on a racetrack.