超音速燃焼器の自発着火に対する支配パラメータの検討

抄録

The dominant parameters of criteria for autoignition in a supersonic combustor with a backward-facing step and perpendicular wall injectors are investigated. The injectant concentration and the residence time within the recirculation region becomes constant value when the momentum ratio exceeds 0.1 at the same spacing of the injectors. The injectant concentration is correlated with the mass flux ratio (ρu )_j /(ρu )_a at different injectant species and total temperature of the main stream, and it is correlated with the ratio of the step height and the momentum thickness H /θ at different step height and boundary layer thickness. The residence time is correlated with the ratio of the step height and the velocity of the main stream H /U_a at any step height, main stream conditions and injectant species. The step height and the location of injectors appropriate to autoignition is predicted by making contour lines of the equivalent ratio and the residence time on L-H plane.