采用多级主火箭的RBCC发动机性能分析(英文)

An investigation on multistage rockets ejection in RBCC engine

采用三维两相数值模拟技术研究火箭基组合推进(RBCC)发动机的燃烧。提出了一种新的主火箭布置方式,该方式采用多级主火箭,一级嵌入到支板之中,另一级置于燃烧室中部上壁面。研究表明,相对于常规的主火箭布局,多级主火箭布局能明显提升发动机性能。置于支板的一级火箭以恰当比工作,起到引射和改善进气道工作特性的作用;二级火箭以富燃状态工作,起到火焰稳定和促进燃烧的作用。多级火箭喷射方案是DAB和SMC模式的综合,可作为火箭引射模态改善二次燃烧一种新的方式。

Three-dimensional two-phase numerical method is used to investigate the combustion processes in RBCC ejector mode.A new structure of primary rockets arrangement（namely multistage rockets ejection） is proposed,i.e.one primary rocket in combustion chamber is embedded in the rearward-facing step at the 50% distance of upper longitudinal wall in combustion chamber,and the other primary rocket,embedded in the center strut.The investigation shows that multistage rockets ejection improve performance of RBCC compared to ordinary rockets structure.At the state of 1st stage rocket working at equivalent ratio and the 2nd stage rocket at fuel-rich state.The results show that the 1st stage rocket not only ejects air from far-field,but also suppresses the chamber pressure affecting the inlet.The 2nd stage rocket ejects the flow in chamber continuously,and works as the flame holder simultaneity.The mechanism of multistage rockets ejection is the optimized combination of DAB and SMC.It may be the better choice under current research of the RBCC engine in ejector mode for secondary combustion.