An Intermittency Transport Model for Practical CFD Designs of High Speed Vehicles

This proposed research is to present a general CFD subroutine for predicting flow transitions in hypersonic regimes. The subroutine makes use of an intermittency transport equation to describe the behavior of the flow transition, and is therefore compatible with existing CFD codes. The proposed model solves an additional transport equation for the intermittency distribution and the resulting intermittency is then used to adjust the turbulent eddy viscosity in the transition region. The major advantage of this approach is that it does not require pre-calculation of the mean flow but includes the laminar, transitional, and turbulent regions in a single computation. The current intermittency transport equation has been validated for subsonic flows with different freestream turbulence intensities and pressure gradients. The Phase I research will extend the capability of the model to high Mach number flight conditions by including compressibility and heat transfer effects. ~000021 ~