Engineering Transition Prediction of a Hypersonic Axisymmetric Boundary Layer

Abstract

for the design of future hypersonic aerospace planes the estimation of maximum heat loads plays an important role. It especially depends on boundary-layer transition for which engineering tools are required at the present time an estimation of transition location in hyper-sonic flow still has to rely on either empirical correlations based on mean-flow properties, or on local, linear stability analysis in conjunction with the e**N method. In any case,a laminar, steady meanflow has to be computed. Each modification of the design requires repeated transition pre- diction and, therefore, repeated computation of laminar, steady mean flows. Because solutions of the full Navier-Stokes equations are verytime consuming, and therefore expensive, one has to choose an approp-riate approximation of these equations. Two common approximations are the parabolized Navier-Stokes equations (PNS) and the thin-layer Navier-Stokes equations (TLNS).