涡轮基组合动力与火箭的耦合特性分析及匹配优化设计

基于高斯伪谱航迹优化方法，建立了"火箭辅助型涡轮基组合动力"的飞行器/推进系统匹配分析方法，针对地面水平起降、以马赫数5巡航的高超声速飞行器，以巡航航程最远为目标，完成了涡轮基组合动力（TBCC）与火箭的耦合特性分析及匹配优化设计。研究结果表明：对于可行的TBCC方案（起飞推重比为1.0），引入合适推力的火箭有助于提升加速爬升段的总效率并降低质量消耗，且对巡航航程有着一定的提升（4%起飞重量推力火箭可增加航程0.97%）；对于不可行的TBCC方案（起飞推重比为0.8），引入火箭不仅可实现推进系统方案的收敛，且其巡航航程相比可行的TBCC方案最多可增加7.9%。考虑到TBCC较大的"死重"和较低的单位迎面推力对巡航性能的不利影响，结构质量占比为25%的巡航型飞行器建议采用"13%起飞重量推力火箭辅助起飞推重比为0.7的TBCC "推进系统。相比之下，结构质量占比为55%的加速型飞行器建议采用" 5%起飞重量推力火箭辅助起飞推重比为0.98的TBCC"推进系统。

Performance coupling analysis and optimal design of rocket-assisted turbine-based combined cycle engines

For the rocket-assisted turbine-based combined cycle engine, an analysis method for matching the vehicle and the propulsion system is proposed based on the trajectory optimization method of the Gauss pseudospectral. For the longest cruise range of the hypersonic aircraft with horizontal ground take-off and Mach number 5 cruise, the coupling characteristics between the Turbine-Based Combined Cycle engine (TBCC) and rocket are analyzed and optimization designs for the rocket-augmented TBCC engine are presented. Results show that for the feasible TBCC scheme (take-off thrust-to-weight ratio of 1.0), introducing a rocket with an appropriate thrust can increase the total efficiency and reduce the total mass consumption during the climb phase, and improve the cruise range slightly (assisted by a rocket of the 4% take-off weight thrust can increase the range by 0.97%).When the TBCC scheme is infeasible (take-off thrust-to-weight ratio of 0.8), introducing a rocket can help the TBCC engine to accelerate the vehicle to the cruise phase, and the cruise range can be increased by 7.9% compared with the feasible TBCC scheme. Considering the negative impact of both the inert weight and the low unit-frontal-area thrust on cruise performance, it is recommended that the cruise vehicle with 25% structural mass ratio adopts a propulsion system of "TBCC (take-off thrust-to-weight ratio of 0.7) assisted by a rocket of the 13% take-off weight thrust". For the accelerating vehicle with a 55% structural mass ratio, it is recommended to adopt a propulsion system of "TBCC (take-off thrust-to-weight ratio of 0.98) assisted by a rocket of the 5% take-off weight thrust".