Question

A positively cambered airfoil is placed in a uniform flow (velocity, \( U_\infty \)) at its zero-lift angle of attack. \( M \) is the corresponding pitching moment. Which one of the following representations accurately describes this scenario?

• A.
• B.
• C.
• D.

Hint:

Even at zero-lift angle of attack, a positively cambered airfoil generates a pitching moment due to the asymmetrical pressure distribution across its surface.

Answer 1

The Correct Option is A

In this scenario, the airfoil is at its zero-lift angle of attack, meaning that it produces no net lift force but still generates a pitching moment. This moment is due to the camber of the airfoil, which leads to an imbalance in the pressure distribution over the surface. The correct representation shows the flow direction and the pitching moment generated by the airfoil in this condition.