Predictions of turbulent mixing in axisymmetric compressible shear layers

Models are described for the turbulent mixing of compressible, axisymmetric shear layers. The models assume that the mixing process is dominated by large-scale coherent structures. These large-scale structures are described locally as linear instability waves. Calculations are made for the development of the axisymmetric shear layer as a function of freestream Mach numbers and velocity and density ratios. The predictions for the axisymmetric shear layer are compared with both experimental measurements and predictions for a plane shear layer. The effects of the initial thickness of the shear layer and the initial amplitudes of the large-scale structures on the growth of the shear layer are examined. The effect of the description of the mean velocity profile is considered.