How do you find drag coefficient without knowing drag force?

The dynamic pressure is multiplied by a characteristic, or reference, area, to produce units of force. The measured drag is divided by the dynamic pressure and also by the reference area, to produce a non-dimensional drag coefficient.

How do you find the coefficient of drag force?

The drag coefficient Cd is equal to the drag D divided by the quantity: density r times half the velocity V squared times the reference area A. The drag coefficient then expresses the ratio of the drag force to the force produced by the dynamic pressure times the area.

How do you calculate drag coefficient using Reynolds number?

Figure 1 graphs the dependence of drag coefficient for a sphere and a cylinder in crossflow on the Reynolds Number Re = ρuD/η, where D is the sphere (cylinder) diameter, η the viscosity of liquid, and .

What does drag coefficient depend on?

velocity
Drag is associated with the movement of the aircraft through the air, so drag depends on the velocity of the air. Like lift, drag actually varies with the square of the relative velocity between the object and the air.

How do you calculate lift and drag coefficient?

The induced drag coefficient is equal to the square of the lift coefficient (Cl) divided by the quantity: pi (3.14159) times the aspect ratio (Ar) times an efficiency factor (e). The aspect ratio is the square of the span divided by the wing area.

Does drag coefficient depend on size?

Factors that Affect Drag. Geometry has a large effect on the amount of drag generated by an object. As with lift, the drag depends linearly on the size of the object moving through the air. The cross-sectional shape of an object determines the form drag created by the pressure variation around the object.

What affects coefficient of drag?

Drag is influenced by other factors including shape, texture, viscosity (which results in viscous drag or skin friction ), compressibility, lift (which causes induced drag ), boundary layer separation, and so on.