Numerical analysis of a ram accelerator employing two-phase combustion

A numerical investigation is carried out of the flowfield around a ram accelerator projectile running through a tube filled with a detonating gas laden with reactive solid particles. First, a mathematical model for the two-phase, chemically reactive flow is proposed. A total variation diminishing numerical scheme is employed, based on the resolution of two Riemann problems: a classical one for the gas phase, and a nonconventional one for the dispersed phase. Results are presented, first for a ram projectile flying at 6.7 km/s through an H2/O2/He mixture, and compared with recent data. Then, computations are made for the same conditions, but with the addition of solid hydrazine nitrate particles. It appears that the existence of sufficiently small particles improve the performance of the ram accelerator.

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