How Does Temperature Affect A Drag Force

Drag force is an aerodynamic force which acts parallel and opposite to the motion of the object when it moves through a fluid. It is caused by friction and differences in air pressure. There are many factors can affect the magnitude of drag force as with aircraft lift. The drag depends linearly on the shape and size of the object moving through the air. The object’s cross-sectional shape determines the form drag which is created by the pressure variation around the object and affects the induced drag of the lifting wing. The surface roughness of the object also affects the amount of drag. The material with smooth and waxed surface will produce less drag than a material with roughened surface. This skin friction effect is included in the measure …show more content…
As with the object lift, drag force varies with the square of the relative velocity. For given-shaped object, generated drag force is affected by the inclination of the object to the flow. Shock wave will be formed around the object when the object moves through the air at the velocity near the speed of sound. It will create an additional drag component which is called wave drag. The motion of the object through the air will cause the formation of boundary layers. Besides that, the viscosity of the air and the air’s mass density are the factors that directly affect the drag force as they will affect the wave drag and skin friction stated above.
Thus, to minimize the drag force, the aircraft is made to be more streamlined and the wings are narrower. The material used to make aircraft also need to have smooth surface. These are because the shape, size and surface roughness of the object will affect the drag. As these conditions decrease, the drag will …show more content…
Engineers reduce friction drag by making the body of the aircraft more streamlined, the wing narrower or by using new materials or manufacturing processes to make the surface of the aircraft smoother. One of the ways to reduce the pressure drag is forcing the boundary layer to become turbulent. The turbulent boundary layer produces greater drag due to friction but can reduce the pressure drag by reducing boundary layer separation. For example, aircraft wings are often engineered with vortex generators on the upper surface to produce a turbulent boundary