A stability based transition prediction criterion for up to Mach 8 hypersonic flows

Laminar-turbulent boundary layer transition has an important impact on wall heat exchange and friction, especially in case of high speed vehicles. Much work has been done to implement efficient transition prediction tools directly into RANS solvers, mostly in the transonic domain. Current work aims at reaching Mach 8 in case of 2D ideal gas flow with a constant Prandtl number, and to develop a criterion based on stability computations taking into account both first and second modes of instability. Model development followed by a first implementation into a boundary layer code will be presented, followed by simple validations. Although the objective is to take into account pressure gradient effects as well as imposed wall temperatures, the first step presented here will be limited to adiabatic conditions.