Meccanica 34: 199–229, 1999. c  1999 Kluwer Academic Publishers. Printed in the Netherlands. OVERVIEWS AND TUTORIALS Edge Singularities and Kutta Condition in 3D Aerodynamics P. BASSANINI 1 , C.M. CASCIOLA 2 , M.R. LANCIA 3 and R. PIVA 2 1 Universit` a di Roma La Sapienza, Dipartimento di Matematica, Ple. A. Moro 5; 00185 Roma 2 Universit` a di Roma La Sapienza, Dipartimento di Meccanica e Aeronautica, v. Eudossiana 18; 00184 Roma 3 Universit` a di Roma La Sapienza, Dipartimento di Metodi e Modelli Matematici per le Scienze Applicate, v. Scarpa 10; 00161 Roma (Received: 2 February 1999; accepted in revised form: 8 March 1999) Abstract. This review paper presents a unified formulation of the Kutta condition for steady and unsteady flows, implemented by removing all unbounded velocity singularities (of power-law and logarithmic type) at the trailing edge, and including nonlinear wakes and thick swept-back wings. A suitable boundary integral approach is adopted and the uniqueness issue is discussed for several wing configurations of interest in aerodynamics. Sommario. Si presenta una formulazione unificata della condizione di Kutta per flussi stazionari e non stazionari, ottenuta imponendo la limitatezza della velocit` a al bordo d’uscita, e valida nel caso nonlineare anche per ali a freccia. Si utilizza un opportuno approccio integrale al contorno e si discute il problema dell’unicit` a per svariate configurazioni alari di interesse nelle applicazioni. Key words: Aerodynamics, Kutta condition, Edge singularities, Boundary integral equations, Fluid dynamics Nomenclature ∇ Ŵ surface gradient; ∇∧ curl operator; α, α(Y ) wedge angle at TE seen from the flow (α > π); β(Y) 1 − π/α(Y); Ŵ wing surface; γ concentrated vorticity; γ(Y) contour on Ŵ (Section 3.1); γ ′ contour on Ŵ (Section 4.2); γ 0 angle between U and T; γ s angle of sweep; c constant multiplying eigenfunctions; c ∞ unit vector along U; δ Dirac distribution;  Laplace operator;  Ŵ Laplace-Beltrami operator; D boundary operator (Section 3.3); ϕ, , ... domain potentials; φ,φ ω , ... surface potentials; [] jump of ;  surface stream function; ν unit vector normal to trailing edge and tangent to W; K, K(Y ), ... circulation;