空间堆Brayton系统旁路阀功率快速调节特性  

Features of transient power regulation by a bypass valve control for a Brayton space nuclear power system

作　　者：马文魁 叶萍 曲新鹤 杨小勇 MA Wenkui;YE Ping;QU Xinhe;YANG Xiaoyong(Key Laboratory of Advanced Reactor Engineering and Safety of the Ministry of Education,Collaborative Innovation Center of Advanced Nuclear Energy Technology,Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学核能与新能源技术研究院,先进核能技术协同创新中心,先进反应堆工程与安全教育部重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2023年第8期1282-1290,共9页Journal of Tsinghua University(Science and Technology)

基　　金：国家原子能机构核能开发项目;中核集团领创项目;国家科技重大专项资助项目(ZX069)。

摘　　要：长寿命、高能量密度和高效率的动力系统是实现未来太空探索目标的必要条件,空间反应堆耦合Brayton系统是兆瓦级空间动力系统的最佳选择之一。功率控制特性是满足系统安全高效运行的关键。该文建立了空间堆Brayton系统动态模型,研究了旁路阀控制下系统的升、降功率特性。结果发现:当载荷变化时,旁路阀控制可快速改变系统局部流量;叶轮机械工况、涡轮和压气机功率及系统电功率能快速响应空间设备的用电需求和负载变化作出相应改变;同时,系统载荷变化导致转动部件对轴的扭矩失衡,容易出现超速事故,旁路控制降低涡轮的输出功率,可有效避免转轴超速的风险。在此基础上,研究了旁路阀开度的敏感性影响,结果发现:系统低压侧和辐射散热回路对旁路阀控制引起的参数扰动最为敏感。旁路阀开度增加后,压气机出口高压气体与涡轮出口低压气体混合,使低压侧管道和部件压力升高;辐射器散热功率增加导致散热回路温度升高,因而辐射器需要更大的散热能力。本研究为空间堆Brayton系统的安全稳定运行提供了参考。[Objective]Long lifespan,compact,high-energy density,and efficient power systems are necessary to achieve future space exploration goals.The space reactor coupled Brayton cycle is high in energy conversion efficiency,small in volume,light in weight,and stable in operation,which is optimal for megawatt space power systems.The power control features are the key to the safe and efficient operation of a Brayton space nuclear power system.The reactor reactivity,inventory,and bypass valve are effective means of system power control.The bypass valve can change the local mass flow rate of a Brayton system and is expected to rapidly control system power to meet the frequently changing load of a space vehicle.[Methods] In this paper,a model of a Brayton space reactor system is established.A system power control simulation program is compiled based on the idea of modular modeling,each component of the system is solved independently,and the mass,momentum,and energy are transferred through data transmission between components.The calculation results of the model in this paper are compared with the simulation results of the startup process in the references,and the accuracy of the program and model is verified.The power-on and power-off transient performance of the system under the control of the bypass valve is investigated,and the effects of the bypass valve opening on system performance are studied,[Results]The power-on and power-off transient results of the system under bypass valve control indicated that bypass valve control could quickly change the pressure and distribution of mass flow rates in the system,the working conditions of the turbine and compressor,and the output power of the system,which could quickly respond to the power demand and load changes of a space vehicle.The change in the load led to a torque unbalance of the shaft,which could further induce rotating shaft overspeed accidents.The strong centrifugal force may damage the blades of the turbine and compressor.The bypass control adjusted the mass flow rat

关 键 词：空间堆 闭式Brayton循环 旁路阀 功率控制 

分 类 号：TL424[核科学技术—核技术及应用]