Combustion in High Speed Air Flows.

Abstract : Progress in the development of analytical models of reacting high-speed flow is described, with specific emphasis on the modeling of reacting two phase flows and the aerodynamics of the ducted rocket configuration. A near dynamic equilibrium, thermal nonequilibrium detailed two phase flow analysis has been developed. Comparison with available data for spray vaporization shows excellent agreement for overall flowfield structure. In addition, the model also provides predictions of spray evolution, in terms of droplet size and number density distribution as a function of distance in the flow. A boron combustion analysis incorporating a model for the finite-rate kinetics of the surface oxidation of boron has been developed. When compared with available data, the model is shown to accurately predict particle burn times as a function of particle size, ambient oxygen concentration, initial particle and gas temperature, and pressure. Analysis of these results demonstrates the critical importance of the chemical and physical property of the particle and its immediate environment. A combined analytical and experimental program has been initiated with the NWC. The objective of this program is to develop a fundamental data base on boron slurry combustion phenomena through the interactive comparison of experimental and analytical results during the program.