The drag of an airfoil at zero angle of attack is a function of density, viscosity, and velocity, in addition to a length parameter

Example

Velocity measurements are made in a 30-cm pipe. The velocity at the centre is found to be 1.5m/s, and the velocity distribution is observed to be parabolic. If the pressure drop is found to be 1.9 kPa per 100m of pipe, what is the kinematic viscosity  of the fluid? Assume that the fluid’s specific gravity is 0.90.

V_CL = V_max = 1.5 m/s

Velocity distribution is parabolic