# 13.1.2: Airfoil design exercise


1. Design an airfoil based on thickness, camber as function of the longitudinal dimension $$x$$.

2. Choose 4 airfoils among the NACA 4-digit series. Plot them, and identify its main characteristics.2

Consider incompressible flow. Consider an aircraft flying at $$h = 11000\ m$$ in a determined incompressible velocity regime (Consider $$M < 0.3$$). The characteristic chord can be considered as $$c = 5\ m$$. The viscosity of air can be considered as $$\mu = 0, 000018\ Ns/m^2$$.

3. Calculate the Reynolds number for those conditions and proceed on with the subsequent analysis.

4. Plot the main characteristic curves of the 5 airfoils (the 4 NACA ones and the one you have defined before). Compare them and discuss the effects of thickness, camber and angle of attack in the generation of lift and drag forces. Check the pressure distribution, the coefficient of pressures and the boundary layer thickness for different angles of attack. Compare all five airfoils by plotting them together.

5. Repeat the previous analysis for different Reynolds numbers. How it affects the aerodynamics of the airfoil?

6. Discuss on the aerodynamic center and the center of pressures of the airfoils.

7. Analyse the stall of the airfoils.

2. Try to combine different cambers and thickness. In particular, choose at least one symmetric airfoil.

13.1.2: Airfoil design exercise is shared under a CC BY-SA 3.0 license and was authored, remixed, and/or curated by Manuel Soler Arnedo via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.