Numerical simulation of compressible homogeneous turbulence

Direct numerical simulations of compressible decaying isotropic turbulence have been performed on a 643 grid. The simulations include a passive scalar with and without a mean scalar gradient. The balances for the equations of second order statistics are used to evaluate the effect of compressiblility on the turbulence. We find that the development of the fluctuations of density and of the dilatational portion of the velocity field are dependent on the initial conditions, and that the compressible terms in the balances vanish rapidly at the Reynolds numbers considered