长征五号运载火箭助推动力系统

长征五号是我国新一代大型运载火箭（代号CZ-5），芯级捆绑四个助推器，每个助推器配置两台并联的液氧煤油高压补燃发动机。本文对国内外运载火箭的故障模式进行分析，结合CZ-5火箭首飞实际情况，提出了助推动力系统风险规避应采取的措施。针对CZ-5火箭助推级和芯一级发动机起动点火的特点，分析了CZ-5火箭首次发射中的异型发动机点火匹配特性。简述了YF-100系列液氧煤油发动机的研制历程、技术特征和热环境适应性，重点分析了发动机在可重复使用和大范围推力调节方面的潜力。对比了国内外液氧煤油补燃循环发动机的推重比性能，分析了不同发动机推重比对火箭运载能力的影响，总结了提高发动机性能的措施（如采用泵后摆技术、选用高强度轻质化材料等）。提出了新一代液氧煤油发动机必须在满足高可靠性的前提下，追求高性能、高推重比、降低成本和增强适应性的后续改进方向。

Booster Stage Propulsion System for Launch Vehicle Long March 5

Long March 5 is China''s new generation of large-scale launch vehicle (code-named CZ-5). The core stage is bundled with four boosters, and each booster uses a dual-unit parallel liquid oxygen kerosene high-pressure staged combustion engine. This article briefly described the technical characteristics of the YF-100 series liquid oxygen kerosene engine and its application in six Long March 5 launches, based on the focus of the difference between launch process and ground hot-test process. The ignition matching characteristics of the different engines in the first launch of the Long March 5 are analyzed. Combined with the failure modes and the adaptability of complex force-thermal environment of the abroad liquid oxygen kerosene staged engines, the risks of liquid oxygen kerosene engines for the first flight of Long March 5 are discussed. It is pointed out that the new generation of liquid oxygen kerosene engine must pursue high performance, high thrust-to-weight ratio, lower cost and enhance adaptability under the premise of high reliability.