Abstract: In order to improve the thrust adjustment level，broaden the use of propellant，enhance the control ability of thrust rocket engine，a GO₂/kerosene variable-thrust rocket engine based on mechanical positioning dual-modulation scheme was designed by using theoretical calculations and ground test methods. The performance of variable-thrust engine and pintle injector，as well as the adjusting effect of mechanical positioning dual-modulation scheme were studied. The results show GO₂/kerosene variable thrust rocket engine achieves stable combustion at 0.26～4.35MPa and generates 57.30～864.70N of thrust. Thrust variation ratio is 15. The maximum combustion efficiency is 97.14%. Besides，the flow control valve can accurately adjust the propellant flow and the pintle injector can actively control the injection pressure drop. Mechanical positioning dual-modulation scheme achieves the desired purpose. The variable thrust rocket engine shows the advantages of the mechanical positioning dual-modulation scheme in the application of the deep variable-thrust technology.

Key words: Rocket engine；Variable thrust；Mechanical positioning dual-modulation scheme；Pintle injector；Gas-liquid injection

摘要： 为了进一步提高变推力火箭发动机推力调节水平、拓宽推进剂使用范围、提升调节控制的技术能力，采用理论计算和地面试验的方法，设计了一款基于机械定位双调系统的气氧/煤油变推力火箭发动机，对变推力发动机的性能、针栓式喷注器的性能和机械定位双调系统的调节效果进行了研究。结果表明:气氧/煤油变推力火箭发动机在0.26～4.35MPa室压实现稳定燃烧，推力变化为57.30～864.70N，推力变化比达到15:1，最高燃烧效率达到97.14%；流量调节阀可精确调节推进剂流量，针栓式喷注器可主动控制喷注压降，达到机械定位双调系统的预期目标，展现出采用机械定位双调系统的该型变推力火箭发动机在深度变推力技术应用的优势。

关键词: 火箭发动机；变推力；机械定位双调系统；针栓式喷注器；气液喷注