核热火箭发动机系统循环方案分析与设计

核热火箭发动机是未来实现载人火星探测的首选动力方案,其具备高比冲、大推力和长工作寿命等优点。我国在此方面研究较少,亟需开展核热推进技术理论及方法的研究。核热火箭发动机系统循环分析与设计是关键问题之一,对推进系统总体设计有重要意义。分析了3种可用于核热火箭发动机系统循环的方案特点,基于闭式膨胀循环设计了比冲为910 s ...

Analysis and design of system cycle for nuclear thermal rocket engine

Nuclear Thermal Propulsion(NTP)is a leading candidate for manned Mars exploration,which offers the advantages of high specific impulse,high thrust and long sustained lifetime for propulsion technology.Due to the limited research in China,it is desiderated to promote the related studies on the theory and methods about NTP.System cycle analysis is one of the major problems,which significantly benefits the overall design of the propulsion system.In this work,the principles,pros and cons of three main cycles for NTP engine were analyzed.Based on the closed expansion cycle,a hydrogen NTP system with Isp being 910 s and another ammonia NTP system with Isp being 390 s were designed.Further,the merits and faults of these two systems were also analyzed,which indicated that the H NTP system is more suitable for manned deep space exploration.For the NH NTP systems,it has advantageous in long-term in-orbit storage of propellant,design difficulty of turbo-pump and nuclear reactor.And it could serve as the substitution of liquid methane oxide engine,being qualified for the long-term and multiple exploration missions with relatively small orbit altitude change.In addition,combining the design procedure and the difference between the cycles of NTP engine and that of chemical engine,several key fundamental issues related to cycle design were proposed,which could provide references for the R&D of NTP engine in our country.