Abstract

Navier-Stokes Based Models in Computational Aeroacoustics

T.K.Kozubskaya, I.V.Abalakin (Institute for Mathematical Modelling RAS, Moscow, Russia); A.Dervieux (INRIA, Sophia Antipolis, France)

e-mail: tata@imamod.ru

The paper is devoted to the comparative analysis of the models intended for direct numerical simulation of noise in compressible gas flows. They are constructed under the assumption that the mean flow field is known. All the models under study are derived on the base of complete Navier-Stokes formulation. The same high accuracy numerical scheme is proposed for the numerical implementation of all the models. It is illustrated that a good efficiency of predictions is provided not only by the scheme accuracy, but also by such computational properties as differential model accuracy and round off errors. The following particular aspects are discussed: the influence of nonlinear effects and the treatment of very small perturbations. Two advanced forms of nonlinear models providing the convergence to linear ones at small solutions are presented.

Section : 7