STOCHASTIC APPROACH FOR MODELING OF NOISE OF TURBULENT FLOWS

A new approach to noise modeling for free turbulent flows is presented . A set of equations is derived from the acoustic variables. In the le ft-hand side of this system, one finds the linearized Euler equations, whereas the right-hand side exibits source terms. These source terms are modeled in using a stochastic space-time description of the three- dimensionnal turbulent motion. The linearized Euler equations includin g a stochastic description of noise sources are solved numerically. Th e Stochastic and Noise Generation (SNGR) model is applied to a subsoni c free jet. The weak interaction between the stationnary mean flow and the acoustic field is taken account. The limitations of the SNGR mode l lie in the statistical properties of the synthetic turbulent field a nd in the use of an axisymmetric modeling of the acoustic propagation.