Stochastically generated turbulence for wall bounded flows

Abstract

An efficient stochastic method is applied to the problem of modelling unsteady turbulent velocity fluctuations within a turbulent flat plate boundary layer. White noise is spatially and temporarily convoluted by the time averaged Reynolds stress tensor and dissipation. The convolutions are conducted such that mean turbulent properties are reproduced and the spectral distribution of turbulent kinetic energy closely matches expected profiles. Wall bounded turbulent flow induces elevated levels of broadband aeroacoustic noise, especially near a sharp edge such as an airfoil trailing edge. In practice, the stochastic method of generating turbulent fluctuations may be used directly to produce turbulent noise sources for further aeroacoustic analysis, thus avoiding costly time dependent simulations of the Navier-Stokes equations. © Austral. Mathematical Soc. 2010.