SHOCKS IN DIRECT NUMERICAL-SIMULATION OF THE CONFINED 3-DIMENSIONAL MIXING LAYER

The occurrence of shocks in the confined three-dimensional turbulent m ixing layer at convective Mach number 1.2 is established by means of d irect numerical simulations. The shocks are generated by the turbulent motions in the flow. Consequently, they can have different shapes and orientations, while they persist for a relatively short time. Further more, they are created by different types of turbulent vortices. The s hocks do not strongly contribute to the turbulent dissipation. Even at the time when the largest shocks occur, the fraction of the turbulent dissipation due to the shocks is less than 10%. (C) 1995 American Ins titute of Physics.