Question

What is the total circulation around the symmetric airfoil according to the thin airfoil theory?

(a) Γ=πα^2cV∞

(b) Γ=π^2αcV∞

(c) Γ=2παcV∞

(d) Γ=παcV∞

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Question is from The Symmetric Airfoil in section Incompressible Flow over Airfoils of Aerodynamics

Answer 1

The correct answer is (d) Γ=παcV∞

Explanation: The total circulation around the symmetric airfoil can be found by integrating the transformed solution γ(θ)=2αV∞\(\frac {1+cos\theta }{sin⁡\theta }\) using ξ=\(\frac {c}{2}\)(1-cosθ)er 0≤θ≤π i.e. Γ=\(\int_0^c\)γ(ξ)dξ=παcV∞.