Langevin Approach to Synthetic Turbulence and Applications

Abstract

We present an analytic scheme, easily implemented numerically, to generate synthetic Gaussian turbulent flows by using a linear Langevin equation, where the noise term acts as a stochastic stirring force. The characteristic parameters of the velocity field are well introduced, in particular the kinematic viscosity and the spectrum of energy. As an application, we study the dynamics of reaction-diffusion systems convected by a turbulent velocity field. It is shown how the propagation velocity and the front roughness are affected by the fluid motion. We also consider phase separation processes under the influence of turbulent stirring.