燃面突变脉冲触发固体火箭发动机不稳定燃烧的数值模拟  

Numerical simulation of the combustion areapulse-triggeredunstable combustion in solid rocket motors

作　　者：魏家琛 范文琦 王兵[1] WEI Jiachen;FAN Wenqi;WANG Bing(School of Aerospace Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学航天航空学院,北京100084

出　　处：《固体火箭技术》2025年第2期195-204,共10页Journal of Solid Rocket Technology

摘　　要：为研究固体火箭发动机燃烧不稳定的触发和驱动机制,基于复合推进剂非均质燃烧特性提出了一种燃面突变脉冲触发不稳定燃烧的物理机制猜想,建立了基于压强耦合响应函数的推进剂燃面质量流率数值模型以及燃面突变脉冲等效数值模型,开展了由燃面突变脉冲触发固体火箭发动机不稳定燃烧的数值模拟研究。结果表明,针对所研究的发动机和推进剂药柱模型,燃面突变脉冲触发了不稳定燃烧现象,在燃烧室内形成以一阶轴向振型为主的压强振荡;压强耦合响应函数和压强指数两个推进剂参数对不稳定燃烧的影响显著,降低这两个参数值均可有效抑制不稳定燃烧现象;燃面突变脉冲的产生概率和强度的增大会明显缩短压强振荡到达极限环的时间;推进剂中的铝(Al)粉对不稳定燃烧中的粒子阻尼作用影响显著。数值模拟结果验证了所提出的物理机制猜想,并基于此提出了抑制不稳定燃烧的可行方法。To investigate the triggering and driving mechanisms of the combustion instabilities of solid rocket motors,atriggering mechanism concerning combustion areapulse was proposed based on the heterogeneous combustion characteristics of composite propellants.The numerical model of the mass flow rate on combustion surface of solid propellants and an equivalent numerical model of combustion area pulse-triggering were established based on combustion response functions.A numerical simulation study on the unstable combustion of solid rocket motors triggered by combustion surface pulse was conducted.The results indicate that for the studied model,the combustion area pulse can trigger unstable combustion,resulting in pressure oscillations primarily characterized by the first-order axial mode in the combustion chamber.The propellant parameters,such as the combustion response functions and pressure exponent,have a significant impact on unstable combustion,and the decrease of these values can effectively suppress unstable combustion.The increase in the probability and intensity of the combustion area pulse significantly shortens the time for the pressure oscillation to reach the limit cycle.The aluminum powder in propellants exhibits a significant influence on particle damping effects during unstable combustion.The numerical simulation results validate the proposed physical mechanism and provide a feasible method for suppressing unstable combustion based on this mechanism.

关 键 词：固体火箭发动机 复合推进剂 燃面突变脉冲 不稳定燃烧 数值模拟 

分 类 号：V435[航空宇航科学与技术—航空宇航推进理论与工程]