F1: Down Force-Technology to drive.... Faster!

[Aditya]

Down Force-Technology to drive.... Faster!



The term "downforce" describes the downward pressure created by the aerodynamic characteristics of a racing car that allow it to travel faster through a corner by holding the car to the track.

The same principle that allows an airplane to rise off the ground by creating lift under its wings is used in reverse to apply force that presses the race car against the surface of the track. This effect is referred to as "aerodynamic grip" and is distinguished from "mechanical grip," which is a function of the car's tires and suspension. The creation of downforce can only be achieved at the cost of increased aerodynamic drag (or friction), and the optimum setup is always a compromise between the two. The aerodynamic setup for a car can vary considerably between race tracks, depending on the length of the straights and the types of corners; some drivers also make different choices on setup. Because it is a function of the flow of air over and under the car, downforce typically rises with the speed of the car and requires a certain minimum speed in order to produce a significant effect. But some cars have had rather unstable aerodynamics, such that a minor change in angle of attack or height of the vehicle (for example, caused by a bump on the track) has caused the car to experience lift, not downforce, sometimes with disastrous consequences.

The amount of downforce that can be created is typically much greater for an open-wheeled Formula One or Indy car than for a full-bodied touring car or stock car because of its enhanced aerodynamic characteristics and the use of wings rather than spoilers.

Two primary components of a racing car can be used to create downforce when the car is travelling at racing speed:the shape of the body, and
the use of airfoils.
Most racing formulae have a ban on aerodynamic devices that can be adjusted during a race, except at pit stops.

Wings

The wings and fins located on most open wheeled race cars are used to create the exact amount of down force and to provide stability to the car at speed. Down force is air friction over the surface of the wing or
fin that pushes the car down in order to keep a car at speed in contact with the racing surface and to slip through the air stream without turbulence. If the wheels tend to spin under acceleration, then more down force is needed. If an open wheeled car is considered not “free” that means that there is too much down force.This robs a car of power and wears the tires excessively. Adjustments to these wings and fins can be done during practice and during the race pit stops to determine at what angle the desired results are
reached.

[Aditya]

More on Wings:



The wings on a Champ Car work opposite to the way they work on an airplane (see How Airplanes Work for details on airplane wings). On an airplane, the wings provide lift. On a Champ Car, the wings are mounted upside down so that they provide downforce. The downforce keeps the car glued to the track with a downward pressure provided by the front and rear wings as well as the body itself. The amount of downforce is amazing -- once the car is traveling at 200 mph, there is enough downforce on the car that it could actually adhere itself to the ceiling of a tunnel and drive upside down! In a street course race, the downforce aerodynamics have enough suction to actually lift manhole covers -- before the race all of the manhole covers are welded down to prevent this from happening.