NUMERICAL-SIMULATION OF RECEPTIVITY PHENOMENA IN TRANSITIONAL BOUNDARY-LAYER FLOWS

A computational fluid-acoustic methodology is described and used to si mulate induced and acoustic receptivity in unsteady boundary-layer flo ws. The methodology solves a finite compressibility form of the Navier -Stokes equations using a flux differenced, finite volume technique, S pecial attention is paid to nonreflective boundary conditions appropri ate for unsteady, multidimensional problems including those involving viscous shear and propagating waves. The numerical experiments include the simulation of acoustic receptivity due to surface inhomogeneity i n which the acoustic phenomena are modeled using physically appropriat e wavelengths, Required steady solution accuracy, convergence accelera tion techniques, boundary condition/flowfield interactions and the cha llenges of scale resolution vs computational cost are addressed in a s eries of simulations, The computed results are shown to be in agreemen t with linear stability theory and experimental measurements.