Joukowski transform: cylinder → airfoil; L = ρUΓ (Kutta-Joukowski)
The Joukowski transform w = z + c²/z maps a circle to an airfoil shape. The complex potential F(z) = U(z + R²/z) e^{-iα} + (iΓ/2π)ln(z) gives the flow. Circulation Γ is set by the Kutta condition (smooth trailing edge). Lift per unit span L = ρUΓ (Kutta-Joukowski, 1902), independent of airfoil shape details.