LIMIT LAYER
As air is viscous, the air particles are 'glued' to the car surface.
The next layer of air particles move slowly on these particles. The next
layer moves a bit more fast and so on. We call this accumulation of air
particles the limit layer.
Now, if the speed of the air through the limit layer is low, the layer
maintains its laminar structure. At great speeds, the limit layer makes
turbulences and dissintegrates. This breaking of the layer consumes energy
and increases the drag factor. However, despite the efforts in the aerodynamic
design, the limit layer destruction is inevitable, althought it may be
displaced behind the car.
DOWNFORCE
This is the vertical component of the air resistence. If we increase
the downforce with wings or "floor effect", we increase the car grip, because
the air pushes it downwards.
FRONT WINGS
These wings create downforce for the front tyres, which increases their
grip. If we increase the angle, the Cd increases and consequently the downforce
applied to the front of the car. The resistence change is small compared
to the resistence created by the rear wing and the speed loss is minimal.
F1 cars have small winglets perpendicular to the front wing. They create
a Venturi tube together with the track and the wing, and therefore increases
downforce due to Bernoulli law.
REAR WINGS
The most important part of the F1 car. If the angle-of-attack (AoA)
of the wing is low, the car will slide off the track, because it will have
small downforce. If the AoA is high, the car will be slow at straights.
We can increase AoA if we're sure that our car will go behind another
car, and the air turbulence behind the other car will 'suck in' our car,
thus cancelling the speed loss. This method is used by F1 drivers to save
fuel.
FLOOR EFFECT
When the air is accelerated below the car floor, due to Bernoulli law,
the pressure below the car is lower than the pressure above the car and
the resultant force is pointed downwards. FIA regulations prohibit the
use of non-plain floors in F1 cars. The teams however place 'air extractors'
below the rear wing and thus create some floor effect.
SUMMARY OF DOWNFORCES
Rear wing: 750 kg
Front wing and the car itself: 320 kg
Floor effect: 300 kg