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MBB2063 January 2012 1 Title Aerofoil test in wind tunnel at different angles of attack. Introduction Aerofoil is a shape of a body that is mainly placed in a stream of air flow or water flow i n order to produce useful aerodynamic effect depending on the usage and need. This shape of aerofoil can be found in many applications and among those include on the airplane wing which helps to produce lift force. In cars, spoilers help to produce down force to ensure the car is connected to ground firmly at high speeds. We can also see the effects of lift and drag forces in a centrifugal compressor blade to produce effective high pressure. This experiment is carried out to review the drag and lift characteristic towards an aerofoil body shape, and how these characteristic can give effect on the body that moves in the air flow. These drag and lift force can give either advantages or disadvantage in our daily life. For example, on the car’s surface, drag force can form at places where it will lead to damages to the car surface when moving at high speeds. In this experiment, we are going to learn how the angle of attack of air against an aerofoil shape can give effect towards the forces acting on the aerofoil and thus allow us to improve the efficiency of a system l ike to reduce the drag effect on the surface. Theoretically, the air that moves or hit the surface will resolve into normal stress and tangential stress. These stresses will cause pressure and shear stress towards the surface. In this experiment, we will find out how these pressures will help affect the lift and drag an aerofoil shape will experience.
