Numerical Simulation of Receptivity Phenomena in Transitional Boundary-Layer Flows
A computational fluid-acoustic methodology is described and used to simulate induced and acoustic receptivity in unsteady boundary-layer flows. The methodology solves a finite compressibility form of the Navier-Stokes equations using a flux differenced, finite volume technique. Special attention is paid to nonreflective boundary conditions appropriate for unsteady, multidimensional problems including those involving viscous shear and propagating waves. The numerical experiments include tbe simulation of acoustic receptivity due to surface inhomogeneity in which the acoustic phenomena are modeled using physically appropriate wavelengths. Required steady solution accuracy, convergence acceleration techniques, boundary condition/flowfield interactions and the challenges of scale resolution vs computational cost are addressed in a series of simulations.