进气道内压缩比对固体燃料超燃冲压发动机性能的影响

为研究固体燃料超燃冲压发动机进气道与燃烧室的匹配特性,以飞行马赫数为6、飞行高度为25km为设计点对发动机各部件进行初步设计,采用数值模拟方法计算了一系列具有不同进气道内收缩比的发动机模型.结果表明:在保持燃烧室结构不变的条件下,发动机推力与比冲随进气道内压缩比增大开始显著下降,随后小幅上升;在保持燃烧室入口面积扩张比不变的条件下,发动机总体性能随进气道内收缩比的增大而提高.在满足进气道起动与燃烧室火焰稳定的前提下,发动机设计应采用尽可能大的进气道内收缩比与尽可能小的燃烧室入口面积扩张比. 

Effect of inlet internal contraction ratio on performance of solid fuel scramjet

To investigate the interaction between inlet and combustor of solid fuel scramjet, various engine components were designed preliminarily at a design point of Mach number of 6 and altitude of 25km. A series of engine models with different inlet internal contraction ratios were simulated numerically. Results show that when the inlet internal contraction ratio increases and combustor structure kept unchanged, the thrust and specific impulse of engine decrease rapidly and increase slightly; with the same area expansion ratio at combustor inlet, the overall performance of engine is improved as inlet internal contraction ratio increases. On the premise of inlet starting and flame holding, the inlet internal contraction ratio should be as large as possible, while the area expansion ratio at combustor inlet should be as small as possible in the engine design.