Transition investigation on hypersonic flat-plate boundary layers flowswith chemical and thermal non-equilibrium

Abstract

The influence of high-temperature gas-effects on hypersonic flat-plate boundarylayer flows is presented in this investigation. Chemical reactions are taken into account and the temperature dependent thermodynamic properties are modelled. The present work investigates for the differences in the spatial disturbance development in a flat-plate boundary-layer flow at M= 20 with ideal-gas properties and for a chemical non-equilibrium case. The comparison of DNS data with linear stability results for the ideal-gas case show good agreement. The non-equilibrium results show a decrease in disturbance levels mostly for the three-dimensional disturbance waves whereas two-dimensional (second mode) disturbances are almost unchanged in their linear amplitudes. © 2006 Springer.