Viscous-inviscid interaction using the parabolized Navier-Stokes equations

A numerical model for the calculation of incompressible viscous flows past airfoils andwings has been developed. The approach is based on a strong viscous-inviscid coupling of aboundary element method with the Navier-Stokesequations in vorticity-streamfunction formulation.A semi-adaptive or fully adaptive grid is used.The interaction is achieved by iterative updatingof the boundary conditions, through the wall transpiration concept. The Navier-Stokes equationsare discretized on a semi-staggered grid.Space-marching integration is performed starting from the stagnation streamline ontwo independent blocks. Results are presented for two different airfoils.Comparisons with experimental results and othercalculations show that the present algorithmperforms well for flows at angles of attack up tomaximum lift and mild separations.