A distinguishing feature of compressible turbulence is the appearance of fluctuations in thermodynamic variables. In many situations of practical and fundamental interest, it can be assumed that the flow is in thermodynamic equilibrium, in which case thermodynamic states can be determined by two thermodynamic quantities alone. When the flow is turbulent, both hydrodynamic as well as thermodynamic variables exhibit nonlinear fluctuations in time and space over a range of scales which increases with the Reynolds number. And, these fluctuations are expected to depend on the level of compressibility in the flow, which is typically quantified by the turbulent Mach number, Mt. We have created a massive database of DNS of isotropic compressible turbulence with resolutions up to 2048^3, Taylor Reynolds numbers up to 400 and turbulence Mach numbers up to 0.6. We have been studied a number of issues and have been able to identify for example a transition at Mt~0.3 where the flow changes qualitatively. We have studied the behavior of temperature, density and pressure statistics as well as the solenoidal and dilatational components of the velocity field. A number of further results can be found in here and here.
Recent exciting results on universality scaling for compressible turbulence can be found here.
Interested in studying full velocity, density, pressure and temperature fields or any other derived quantity from these DNS? Contact Dr. Donzis to get access.