Automotive Aerodynamics

IntroductionWhen objects move through air,

forces are generated by the relative motion between air and surfaces of the body, study of these forces generated by air is called aerodynamics.

Forces on a Automotive Body

Four kinds of forces may act on a body:LiftDragWeightThrust

Forces on a Automotive Body

Four kinds of forces may act on a body:LiftDragWeightThrust

Lift

It is the sum of all the dynamic forces on a body normal to the direction of external flow around the body.

F=(1/2)CLV2A ρ

DragIt is the sum of all the dynamic forces

in the direction of fluid flow, so it acts opposite to the direction of object.

F=(1/2)CDV2A ρ

WeightIts just the weight of the object in

motion. It affects the acceleration of the object.

ThrustForce produced in the opposite

direction to drag that is higher than drag so the body can move through the fluid(air).

History

Today’s Car

Effect of Aerodynamic Drag on Engine Performance

Aerodynamics Design TipsKeep the vehicle low to ground.Cover the wheel wells.Avoid open AreasMake corners round instead of sharp.The body should be as smooth and

continuous as possible.The should be no sharp angles.

Aerodynamics Design TipsFront screen should be raked as much as

is practical.All body panels should have a minimal

gap.Make use of spoilers.

For Vehicle you Already ownKeep your vehicle washed and waxed

(reduces skin friction).Remove mud flaps from behind the

wheels.Add a spoiler to the front or rear of the

car.Drive in closed sun roof and windows.

Benefits of Aerodynamically designed VehicleMore EfficiencyMore Speed (increased performance)More stability (even at higher speeds)Good Looking (Design Improvements)

Thank You!!!

Thank You!!!