Introduction to Flight 7th Edition by John Anderson

تمرين 6

The ratio of lift to drag L / D for a wing or airfoil is an important aerodynamic parameter; indeed, it is a direct measure of the aerodynamic efficiency of the wing. If a wing is pitched through a range of angle of attack, L/D first increases, then goes through a maximum, and then decreases. Consider an infinite wing with an NACA 2412 airfoil. Estimate the maximum value of L/D. Assume that the Reynolds number is 9 x 10 6.