Aerodynamics in automobile

KEVIN GEORGE

INH10ME064

What's the 1st thing that comes to your mind?

Aerodynamics is a sub-field of fluid dynamics which is a study of how gases interact with moving bodies.

Applications can be so vast ranging from

Automobile( aero planes, cars ,trucks, ships etc..) Architecture( bridges, buildings etc..) Sports Numerical weather prediction

Study of the aerodynamics of road vehicles

Goals

reducing Drag (attain high speeds)

minimizing noise emission,

preventing undesired lift

Improve stability at high speeds and produce down force .

• The term down force describes the downward pressure created by the aerodynamic characteristics of a car.

• It allows it to travel faster through a corner by holding the car to the track or road surface.

• It is the vertical component of the force acting downwards, which arises due to the airflow over and below the car’s surface

Front wing

The front wing or the spoiler is the first part of the car that makes contact with the air.

It affects the airflow in the full length of the car and even tiny changes can have huge effects on the overall performance.

Proves 42% of total down force

Aerofoil in Aeroplanes

Aerofoil in F1 cars

Rear Wing

The rear wing helps glue the rear wheels to the track, but it also can hugely increases drag (air residence against the body of the car). But designers are constantly working to use as little angle of incidence on the rear wing as possible without harming overall performance.

Diffuser

The diffuser or floor, is designed to ensure the smoothest exit for the air that is flowing under the car. Designers come up with a huge variety of complicated shapes because the quicker the air exits, the more down force the car generates, and the higher the grip will be.

Wind tunnel testing

Wind tunnels operate below the speed of sound and the airstream is created by large motor-driven fans. At velocities near or above the speed of sound, the airstream is created either by releasing highly compressed air from a tank at the upwind end of the tunnel testing area, or by allowing air to rush through the tunnel into a previously created vacuum tank at its downwind end.

ANSIS, CATIA, ALIAS STUDIO

ANALYZE CHANGES DURING DESIGN PHASE AND DEVELOPMENT

REDUCES TIME TO DEVELOP OPTIMAL DESIGN

ABLE TO STUDY INDIVIDUAL ELEMENTS MORE EFFECTIVELY

Advantages:

Reduces drag improves fuel economy. stability at high speed improving the traction especially at

corners to allow variable cornering speed. Improves Aesthetic value Reduces noise

Disadvantages:

Understeer causes the car to go straighter than thetrajectory that the driver is trying to take.

Oversteer is when the rear wheels of a car do not trackbehind the front wheels. Instead, they tend to slide outtowards the outside of the turn. This can easily cause a carto spin.

“ENHANCEMENT OF AERODYNAMIC PERFORMANCE OF A FORMULA-1 RACE CAR USING ADD-ON DEVICES”, B. N. Devaiah, S. Umesh, SASTECH journal