摘要
一次火箭射流与二次空气流之间的主次流相互作用是火箭基组合循环(RBCC)发动机引射模态工作过程的主导机制,对引射模态性能具有关键性影响。基于典型支板火箭RBCC发动机特征流道模型,进行了三种不同支板火箭构型的宽工况冷喷流引射试验,获得了引射进气特性、主次流相互作用特性与规律。研究结果表明:随着一次流流量、总压比增加,二次流引射进气马赫数逐渐增大,流量逐渐增加至某一最大值,而引射比持续单调减小;无量纲分析显示,单矩形喷管的支板火箭构型相对于双圆形喷管构型具有更强的引射能力,在相同一次流流量与喷管喉道面积时能提高10%~40%的流量通量比,且支板尾缘带波瓣凹槽结构有利于提升引射能力。从主次流内流过程来看,随着一次流流量、总压比增加,内流道压力分布整体上逐渐降低,马赫数分布逐渐提高,反映出内流加速降压、引射进气流量增加的过程,同时下游的引射增压比呈增大趋势,以更大的总压损失为代价;相同一次流流量时,单矩形喷管构型相对于双圆形喷管引起的内流道压力更低、马赫数更高,实现基本相当的引射比时总压恢复系数相对更高。随着主次流总压比的增加,主次流的速度比和对流马赫数呈现减小的趋势,而压比和密度比则有所增加;双圆形喷管构型时速度比和对流马赫数明显高于单矩形喷管构型,而压比和密度比则相对更低;这些参数梯度变化在初始状态层面上决定了主次流相互作用的过程及其宏观特性。
The primary-secondary flow interaction(PSFI)is the dominant mechanism of the rocket-based combined cycle(RBCC)engine’s ejector mode operation,which plays a crucial influence on the ejector mode performance.Based on a typical strut-jet RBCC flowpath model,cold ejecting experiments on three different strut-jet configurations were conducted under a wide-range conditions of primary jet,the ejecting inflow charac⁃teristics,and primary-secondary flow interaction characteristics were obtained.The results show that with the in⁃creasing primary mass rate and total pressure ratio,the secondary inflow Mach number gradually increases,and the mass rate synchronously increases to a certain upper limit,while the entrainment ratio is decreased monotoni⁃cally.As indicated by non-dimensional analysis,the single rectangular nozzle configuration shows a stronger ejecting capability than the double circular nozzle configuration,the mass flux ratio increases by 10%to 40%at the same primary flow rate and nozzle throat area,and the lobe groove structure on the trailing edge of strut is con⁃ducive to improve the ejecting capability.From the perspective of the PSFI internal flow processes,with the in⁃creasing primary mass rate and total pressure ratio,the flowpath pressure distribution is gradually decreased and the corresponding Mach number increases,which reflects the internal flow’s velocity increase and pressure de⁃crease corresponding to the increasing secondary mass rate.The downstream ejecting pressure ratio due to prima⁃ry-secondary flow interaction shows an increasing trend,with a cost of larger PSFI total pressure loss;under the same primary mass rate,the single rectangular nozzle configuration has lower flowpath pressure and higher Mach number than the double circular nozzle configuration,meanwhile,the total pressure recovery is relatively higher when achieving a considerable level of entrainment ratio.With the increasing PSF total pressure ratio,the veloci⁃ty ratio and convective Mach number show a decreasi
作者
罗飞腾
姚达豪
李新珂
渠镇铭
陈文娟
龙垚松
LUO Feiteng;YAO Dahao;LI Xinke;QU Zhenming;CHEN Wenjuan;LONG Yaosong(School of Aerospace Engineering,Huazhong University of Science and Technology,Wuhan 430074)
出处
《推进技术》
EI
CAS
CSCD
北大核心
2024年第12期115-131,共17页
Journal of Propulsion Technology
基金
国家自然科学基金面上项目(52076094)。
关键词
火箭基组合循环发动机
主次流相互作用
引射模态
支板火箭
实验研究
Rocket-based combined cycle(RBCC)
Primary-secondary flow interaction(PSFI)
Ejec⁃tor mode
Strut-jet rocket
Experimental study
