Turbulent drag just on region 2, denoted as (Df,2)turbulent, refers to the aerodynamic drag caused by friction between a turbulent flow and the surface of a specific region 2 on an object, such as an airfoil or wing. This drag arises due to the chaotic and irregular motion of the fluid particles in the turbulent flow interacting with the surface of the designated region.Â
- (Df,2)turbulent: Turbulent skin friction drag just in region 2
- q∞: Dynamic pressure of the freestream flow
- c: Chord length of the object
- (Cf,c)turbulent: Skin-friction drag coefficient under turbulent flow conditions in region 2
- x1: Characteristic length of region 1
- (Cf,1)turbulent: Skin-friction drag coefficient under turbulent flow conditions in region 1