A zonal characteristic boundary condition for numerical simulations of aerodynamic sound

This paper presents a non-reflecting boundary condition that significantly reduces the spurious pressure oscillations that are produced when vortical structures in a compressible flow cross the computational farfield boundaries. The method is based on commonly used characteristic boundary conditions. Here, incoming characteristics are ramped to...

Direct numerical simulation of the flow around an airfoil with unsteady wake

Direct numerical simulations of a NACA-0012 airfoil at zero degrees incidence are presented for a range of Mach and Reynolds numbers. At Reynolds number 10,000, the flow around the airfoil is found to be dominated by vortex shedding from an unstable wake. Frequencies are found to collapse using a Strouhal number based on trailing edge...

Noise due to unsteady flow past trailing edges

This paper presents two-dimensional direct numerical simulations (DNS) of noise generated at trailing edges (TE) with zero thickness. The simulations are conducted specifying either no-slip or slip walls in order to investigate viscous effects. In both cases, small amplitude disturbances are introduced close to the inflow boundary that serve as...