两级入轨RBCC等动压助推弹道设计与推进剂流量分析  

RBCC constant dynamic pressure booster trajectory design and propellant mass flowrate analysis for TSTO transportation system

作　　者：薛瑞[1] 胡春波[1] 吕翔[1] 秦飞[1] 

机构地区：[1]西北工业大学燃烧热结构与内流场重点实验室,西安710072

出　　处：《固体火箭技术》2013年第2期155-160,共6页Journal of Solid Rocket Technology

摘　　要：火箭基组合循环(RBCC)发动机的性能与飞行器相互耦合,导致RBCC发动机的设计研制需要针对相应的飞行弹道。对RBCC飞行器助推段等动压弹道设计方法进行研究,根据动力学和运动学方程式,提出了基于高度步长的等动压轨迹计算方法。利用提出的助推段轨迹设计方法建立了弹道计算程序,进行了以RBCC作为第一级动力的两级入轨飞行器助推段(Ma=0～8)飞行弹道仿真;根据仿真结果,采用遗传算法/序列二次规划联合优化策略,以推进剂最省为目标对非等动压爬升段RBCC发动机最优流量控制方案进行了研究。计算结果表明,所建模型及计算方法考虑了发动机与飞行轨迹的耦合作用,可用于RBCC助推段弹道设计;整个助推段推进剂消耗占飞行器起飞质量的55%,推进剂消耗主要发生在非等动压飞行段,非等动压段与等动压段的消耗量之比为2.3;经弹道优化后的推进剂利用率提高了3.5%;在引射模态(Ma=0～2.5)最优的一次火箭的调节比为4.3,一次火箭进入亚燃模态后要迅速节流,最低流量需求发生在引射/亚燃模态转换期间。Due to the coupling of rocket based combined cycle （RBCC） engine performance with flight vehicles, the design and the development of RBCC engines should be done for different flight trajectory. Based on the equations of dynamics and kinematics, the constant dynamic path design methodology of boost trajectory for vehicles powered by RBCC engines was studied and the altitude- step walking method was established. The simulation of the trajectory of the first stage flight vehicle powered by RBCC engine in a Two-Stage-To-Orbit （TSTO） hypersonic space transportation for Ma =0 ~ 8 was made by the program designed in C ＋ ＋ language. According to the baseline trajectory, with the coupling optimization strategy of Genetic Algorithm/Sequential Quadratic Programming, a propellant flowrate control history that minimizes the propellant consumption for the non constant dynamic pressure flight path was calculated. The results show that considering the coupling between RBCC engines and flight path, the computation model can be used for the RBCC boost trajectory design and analysis;The whole boost process can consume as high as 55% takeoff mass propellant, in which the mass ratio of non-constant-dynamic-pressure segment to constant-dynamic-pressure segment is 2.3 ; Through optimization, the efficiency of propellant consumption can be enhanced by 3.5% ;In ejector mode （Ma = 0 -2.5 ）, the optimum mass flowrate regu- lative ratio of primary rockets is 4.3. The mass flowrate of primary rockets should be throttled when RBCC engines transit from inject to ramjet mode operation and the minimum mass flowrate is needed during the mode transition process.

关 键 词：火箭基组合循环 高超声速飞行器 等动压飞行 弹道优化 推进剂流量控制 

分 类 号：V438[航空宇航科学与技术—航空宇航推进理论与工程]