超燃冲压发动机模态转换及推力突变实验研究  

Investigation of mode transition and thrust performance in transient acceleration and deceleration experiments

作　　者：连欢 顾洪斌[1] 周芮旭 李拓 李忠朋 LIAN Huan;GU Hongbin;ZHOU Ruixu;LI Tuo;LI Zhongpeng(State Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences,Beijing100190,China;University of Chinese Academy of Sciences,Beijing101408,China)

机构地区：[1]中国科学院力学研究所高温气体动力学国家重点实验室,北京100190 [2]中国科学院大学,北京101408

出　　处：《实验流体力学》2021年第1期97-108,共12页Journal of Experiments in Fluid Mechanics

基　　金：国家自然科学基金(11872366,91941104);中国科学院前沿科学重点研究项目(QYZDJ-SSW-JSC022)。

摘　　要：针对双模态冲压发动机燃烧室模型开展了来流连续变化飞行马赫数5.0~6.0加速上行和6.0~5.0减速下行的地面直连试验研究。首先基于直连台架推力及时间离散质量加权沿程马赫数一维计算,观察到了加速上行过程中来流变化导致的亚燃-超燃工作模态转变及推力突变现象;通过高速纹影流动显示技术及流动特征提取,提炼了来流变化导致模态转换及推力突变过程中瞬态流动特征的发展规律;最后通过超声速核心流激波强度理论以及压比时空图对动态飞行轨迹模态转换及推力突变机制进行了讨论,研究结果表明:释热总量与内流道匹配是模态转换及推力变化过程的根本,主导流动特征是隔离段预燃激波强度演变特性,然而燃料横向射流气动节流以及释热反压在隔离段预燃激波削弱耗散之后,仍然可对来流进行减速并维持推力。同时,动态飞行轨迹气动热及燃烧热积分效应可改变热流边界层特性以及发动机内流道抗反压能力,造成亚燃与超燃工作边界变化。Experiments are designed to investigate the transient fluid-combustion phenomenon during simulated transient acceleration and deceleration between flight Ma 5.0~6.0.Flow induced ram-scram mode transition and thrust abruption were observed.The transient fluid-combustion evolutions were characterized with high speed Schlieren imaging and summarized into four phases.The fluid phenomena were discussed based on the impulse function analysis.The accumulated heat release from the thermodynamic cycle analysis dominates the mode transition and thrust abruption process.The isolator pseudo-combustion shock train system is the dominating flow feature during the mode transition.The backpressure induced by the supersonic crossflow contributes to maintain thrust.In addition,the heat transfer and boundary layer disturbance could shift the combustion mode transition limits.

关 键 词：变马赫数 双模态冲压发动机 模态转换 推力突变 瞬态流动特征 

分 类 号：V433.9[航空宇航科学与技术—航空宇航推进理论与工程]