Eddy Viscosity-Intermittency Factor Approach to Numerical Calculation of Transitional Heating on Sharp Cones in Hypersonic Flow

摘要

Analysis of laminar, transitional, and turbulent boundary layers on a sharp cone at zero angle of attack under hypersonic perfect gas conditions is presented. The governing boundary-layer equations were numerically integrated on a digital computer using a marching, iterative, implicit, finite-difference method. The turbulent boundary layer is analyzed using a two-layer eddy viscosity model with a constant turbulent Prandtl number, and the transition region is treated through an eddy viscosity-intermittency factor approach. Comparison with experimental data reveals that the approach yields an accurate description of laminar, transitional, and fully turbulent heat transfer on sharp cones in the Mach number range from 5 to 10 under cold wall conditions. Verification of the detailed calculation of transitional and turbulent boundary-layer structure under hypersonic conditions must await further experimental investigations. It appears that the eddy viscosity approach to calculation of transitional and turbulent boundary layers may indeed be applicable and accurate under hypersonic conditions. (Author)