Skin-friction drag coefficient for the bottom surface Calculator

The skin-friction drag coefficient (Cf) is a dimensionless parameter used in aerodynamics to quantify the amount of skin-friction drag generated by the frictional resistance between a solid surface and the fluid (such as air) flowing over it. It provides a standardized way to express the skin-friction drag relative to the dynamic pressure of the fluid and the size of the object’s surface area. 

• Cf: Skin-friction drag coefficient
• Df,bottom: Skin-friction drag on the bottom surface
• q∞: Dynamic pressure of the freestream flow
• S: Wing Area