EXPERIMENTAL, ANALYTICAL, AND COMPUTATIONAL METHODS APPLIED TO HYPERSONIC COMPRESSION RAMP FLOWS

Experimental data on fully laminar and transitional shock-wave/boundar y-layer interactions in two-dimensional compression corners are provid ed and used for the validation of two full Navier-Stokes solvers, as w ell as for checking the capabilities and limitations of simple analyti cal prediction methods. Viscous pressure interaction, free interaction , and inviscid oblique shock theory are found to predict well the pres sure levels on the flat plate upstream of the interaction, within the separated region, and downstream of the interaction, respectively. The reference temperature theory is found to perform well in attached flo w regimes both upstream and downstream of the interaction region and t o provide the basis for a universal peak heating correlation law. Full Navier-Stokes computations are necessary, however, to predict the ext ent of the interaction region and the associated influence on the pres sure distribution (control effectiveness) as web as the detailed heat transfer distribution. To achieve this, very fine gridding coupled wit h the use of strict convergence criteria (based on the evolution of th e location of the separation point rather than on standard density res iduals) is shown to be necessary. It is finally shown that, although s ophisticated turbulence models need to be further developed before the detailed characteristics of fully turbulent shock-wave/boundary-layer interactions may be predicted, transitional interactions (where trans ition typically occurs in the neighborhood of reattachment) may be ade quately handled by algebraic turbulence models ''switched on'' just do wnstream of reattachment.