NAVIER-STOKES HEATING CALCULATIONS FOR BENCHMARK THERMAL PROTECTION SYSTEM SIZING

A study was carried out to identify, select, and benchmark simulation techniques needed for thermal protection material selection and sizing for reusable launch vehicles. Fully viscous, chemically reacting, Nav ier-Stokes solutions for the flow around a sphere are generated and co mpared using three different flow solvers. The effects of grid resolut ion, algorithm, transport modeling, and surface boundary conditions on the magnitude and convergence of the predicted heat transfer rate are examined, A third-order Van Leer inviscid upwind flux formulation was found to be a good method for surface heat transfer predictions. A nu mber of three-dimensional, chemically reacting, Navier-Stokes flow sol utions are generated for the nose of a single-stage-to-orbit rocket at angle of attack. A methodology for thermal protection system material selection is demonstrated. Tile strong influence of thermal protectio n system material selection on predicted heat transfer rates and surfa ce temperatures is demonstrated, Further, it is shown that the changes in surface emissivity and catalycity at the interfaces between differ ent thermal protection system concepts can produce large jumps in the predicted surface temperature, These gradients must be accounted for i n the thermal protection system and vehicle design process.