Accumulation of Disordered Perturbations of Density, Velocity, and Pressure in an Unstable System

Abstract

A numerical study of the behavior of disordered perturbations of density, velocity, and pressure in a problem of the flow around a stationary solid sphere is carried out. Regular equations of multimoment hydrodynamics supplemented with stochastic components are used for the study. The statistical properties of stochastic components are identified with the statistical properties of disordered perturbations arising in the incoming flow due to an external influence. It is found that the loss of stability is accompanied by the accumulation of disordered perturbations of density, velocity, and pressure in the wake behind the sphere. It is shown that high values of the turbulence coefficient provide a significant accumulation of disordered perturbations, which leads to a strong distortion of the laminar flow pattern. It is found that high values of the pressure and density pulsation coefficients provide an equally significant accumulation of disordered perturbations in the pressure and density.