Quasi-One-Dimensional Prediction during Ramjet-mode Operation in Diverging Dual-mode Combustors

Abstract

A quasi-one-dimensional model is proposed to predict a thermal choked flow-field with a pseudo-shock wave system (ramjet-mode operation) in diverging dual-mode combustors. To predict pressure-rise upstream of the injector through the pseudo-shock wave system, the model used an empirical correlation between the penetration length of the pseudo-shock wave system and the rise in pressure. In addition, to predict the thermal choking location in diverging combustors, the model used the combustion efficiency distribution against a streamwise location, which was deduced from the combustion test results reported in the present study. Results indicate that the model simulates ramjet-mode operation with a reasonable degree of accuracy by correlating of the pseudo-shock wave system and combustion efficiency distribution.