Question

The Kutta Condition according to the thin airfoil theory is_____

(a) γ(c)=0

(b) γ(x)=0

(c) γ(ξ )=0

(d) \(\frac {dz}{dx}\)=0

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I'm obligated to ask this question of The Symmetric Airfoil in division Incompressible Flow over Airfoils of Aerodynamics

Answer 1

Right choice is (a) γ(c)=0

The explanation is: The Kutta Condition says the flow leaves the trailing edge smoothly. The trailing edge is at chord length c for a thin airfoil which gives γ(c)=0. Also, γ(x)=0 or γ(ξ)=0 is not true for all x or ξ. \(\frac {dz}{dx}\)=0 is the definition of the symmetric airfoil, not Kutta condition.