NUMERICAL MODELLING OF KINETICS-TURBULENCE INTERACTION IN HIGH MACH NUMBER FLOWS

WE PROPOSE TO DEVELOP METHODS TO SOLVE ONE OF THE CRITICAL PROBLEMS OF TURBULENCE MODELLING INVOLVED IN HYPERSONIC FLOW IN WHICH ALL TRADITIONALLY USED TURBULENCE MODELS FAIL, NAMELY MODELLING OF KINETIC MIXING AND CHEMICAL REACTION PROCESSES IN HIGH MACH NUMBER (MA-25) TURBULENT FLOWS. WE PROPOSE TO DEVELOP DIFFERENTIAL TRANSPORT MODELS BASED ON OUR NEW RENORMALIZATION-GROUP (RNG) THEORY FOR TURBULENT HEAT, MASS, MOMENTUM TRANSFER COMBINED WITH CHEMICAL REACTION PROCESSES FOR HIGH MACH NUMBER FLOWS. PRELIMINARY RESULTS FOR APPLICATION OF THESE NOVEL, NEW MODELS TO NON-STATIONARY AND SEPARATE INCOMPRESSIBLE AND COMPRESSIBLE FLOWS, INCLUDING FLOW OVER A BACKWARD-FACING STEP, OSCILLATORY PIPE FLOW, SHOCK-INDUCED SEPARATION ON AIRFOILS, AND LOW AND HIGH PRANDTL NUMBER TURBULENT HEAT TRANSFER SUGGEST THAT THE MODELS WILL BE VERY EFFICIENT FOR THE PRESENT CLASS OF DIFFICULT FLOW PROBLEMS. IN ADDITION, RECENT EXTENSIONS OF THE RNG METHOD GIVE A DESCRIPTION OF TURBULENT COMBUSTION THAT PROMISES SIGNIFICANT ADVANCES IN OUR ABILITY TO MODEL REACTING FLOW PROBLEMS.