火箭推进

介绍了国外单组元变推力发动机的应用现状,阐释了单组元变推力发动机的结构和设计原理,总结了研制和改进过程中的关键技术,主要包括径向双层夹套催化床设计、径向喷注器设计、流量稳定调节技术和催化床空穴控制技术等。美国为火星软着陆研制的MR-80和MR-80B无水肼单组元变推力发动机分别应用于“海盗”号和“好奇”号着陆器下降级推进系统。MR-80发动机可实现275～2 835 N变推力调节,推力变比为10:1,比冲为205 s,呈120°均布于“海盗”号着陆器三角形基座的长边。“好奇”号下降级推进系统由2个高压氦气瓶、3个推进剂贮箱、8台单组元变推力发动机、8台单组元250 N姿控发动机、1个压力控制组件和3个推进剂控制组件组成,MR-80B发动机可产生31～3 603 N的真空推力,推力变比达到100:1,比冲范围为204～223 s。

The application status of the foreign monopropellant throttling engine was introduced.The structure and design principles of the monopropellant throttling engine were explained.The key technologies in the development and improvement process were summarized, mainly including the radial double-layer catalyst bed design, radial injector design, flow stability regulation technology and catalyst bed void control technology.The MR-80 and MR-80B monopropellant throttling hydrazine engines developed by the United States for soft landing on Mars were used for the “Viking” and “Curiosity” lander descent stage propulsion systems respectively.The MR-80 engine can produce a throttleable thrust range from 275 N to 2 835 N with the capability of 10:1 throttling and the specific impulse of 205 s, distributed at 120° on the long sides of the “Viking” lander triangle base.The “Curiosity” lander descent stage propulsion system consists of two high-pressure helium tanks, three propellant tanks, eight monopropellant throttling engines, eight 250 N reaction control system engines, one pressure control assembly and three propellant control assemblies.The MR-80B engine can produce the vacuum thrust range from 31 N to 3 603 N with the capability of 100:1 throttling and the specific impulse of 204～223 s.