Parallel Compatible Transition Closure Model for High-Speed Transitional Flow

A single-point transition closure model that incorporates analytical results by stability theory in a reasonably wide range of Mach numbers has been formulated for supersonic/hypersonic boundary-layer flows, which includes two transport equations to specify the transition onset locations: one for the eddy-viscosity coefficient of laminar fluctuations and another for intermittency factor. The effects of compressibility are modeled through solutions of laminar self-similar boundary layer at subsonic and supersonic conditions with a totally local closure. Then, to form a complete transition turbulence model, the proposed transition model is coupled with the compressible k-omega shear stress transport turbulence model. In the end, several sets of well-documented flow cases are chosen to validate the present transition model, and the results are in satisfactory accord with experimental data. Proven by the numerical tests, the present model is capable of predicting well the supersonic/hypersonic transition onset that is dominated by the first and second Mack instability modes and laminar separation mode.