2. Aerodynamics

Airfoil Theory — Quiz

Test your understanding of airfoil theory with 5 practice questions.

Practice Questions

Question 1

At what chordwise location along the airfoil is the aerodynamic center (about which the pitching moment is independent of angle of attack) located according to thin-airfoil theory?

Question 2

For a symmetric airfoil in thin-airfoil theory, calculate the lift coefficient $C_L$ at an angle of attack of $6^\circ$. Show your calculation.

Question 3

A cambered airfoil has zero-lift angle $\alpha_{L0}=-3^\circ$ and lift-curve slope $a_0=2\pi\,(\mathrm{rad}^{-1})$. At an angle of attack $\alpha=5^\circ$, what is $C_L$? Show your calculation.

Question 4

How is the pressure coefficient $C_p$ at a point on an airfoil surface defined?

Question 5

If the local surface velocity is $V=60\,\mathrm{m/s}$ and the freestream velocity is $V_\infty=50\,\mathrm{m/s}$, what is the local pressure coefficient $C_p$ using the relation $C_p=1-(V/V_\infty)^2$? Show your calculation.