空气涡轮火箭发动机内外涵气流掺混研究

通过无化学反应、均匀进气条件下肼单组元空气涡轮火箭发动机混流燃烧室内流场的数值计算,得到了流向涡与正交涡系产生、衰减演变过程及其对内外涵气流掺混效率的影响规律。结果表明,大尺度阵列二次环流诱导形成的流向涡对内外涵气流掺混起主导作用,大波瓣穿透率的斜切波瓣混流器的综合性能较优。结合热试车结果,分析了包括波瓣混流器在内的两类掺混方案的强化掺混效率。分析表明,非均匀进气条件对小尺寸空气涡轮火箭发动机掺混燃烧效率影响很大。

Research on turbulent mixing of the bypass and core flows for air-turbo-rocket

A numerical calculation on the flow field of mixing combustion chamber without chemical reaction was carried out for hydrazine monopropellant air-turbo-rocket under uniform inlet flows.The induction and decay evolution of streamwise and normal vortices were obtained,and an analysis was made on the influence of this course on turbulent mixing efficiency of the bypass and core flows.A quantitative analysis revealed that streamwise vortices induced by a spanwise array of large scale secondary flows at trailing edge play a dominant role in the downstream mixing process of the bypass and core flows.It is preferable to employ scarfed lobed mixers with large lobe penetration rate.A preliminary analysis of turbulent mixing efficiency was also made between computational and experimental data for two mixing schemes including three kinds of lobed mixer,and results show that nonuniform inlet flow conditions have a significant impact upon turbulent mixing and combustion efficiency for small dimension air-turbo-rocket.