A Quasi-Continuous Vortex Lattice Method for Unsteady Aerodynamics Analysis

Variation of leading-edge suction during stall for unsteady aerofoil motions

“…In the current formulation, U ref is set equal to the forward velocity, which is the component of the aerofoil's velocity in the negative X direction. Although recent research efforts (Xia & Mohseni 2017;Epps & Greeley 2018;Epps & Roesler 2018;Taha & Rezaei 2019) have provided updates to the Kutta condition at the trailing edge, the current formulation, which is based on the approach of Katz and Plotkin (Katz & Plotkin 2000), assumes zero vortex-sheet strength at the trailing edge, and implicitly enforces the Kutta condition by imposing a zero vortex strength at each time step at the trailing edge. The Fourier coefficients are determined using the instantaneous local downwash on the aerofoil due to all bound and shed vorticity by enforcing the boundary condition that the flow must remain tangential to the aerofoil surface:…”