MODELS OF TURBULENCE FOR THE DESCRIPTION OF A FLOW IN A JET OF COMPRESSIBLE GAS.

The authors propose a different mechanism for the influence of dynamic compressibility on turbulent mixing, which is associated not with a change in the balance of kinetic energy, but with a change in the structure of the large-scale vortices, i. e. , with a change in the low-frequency part of the fluctuation spectrum. Two differential models of turbulence, in which Kovazhnyi's differential equation for turbulent viscosity appears, are modernized on the basis of this mechanism. The proposed models are tested by a comparison between the results of numerical calculations and experimental data as the Mach number of the outflow and the relative heating of the jet are varied.