兆瓦级大型天基核动力系统方案设计研究

Conceptual design of megawatt class large-scale space nuclear power system

轨道和行星探索任务需要强大、可靠和耐用的能量,而空间核反应堆是空间推进能量密度最高的方式之一。文章提出了一种新型兆瓦级天基核动力系统的概念设计,热源采用功率为3.6 MW的快中子能谱反应堆,堆芯由氦氙(He-Xe)混合气体进行冷却,采用以He-Xe为工质的双环路闭式布雷顿系统进行能量转换,此外还开展了废热排放关键设备的结构设计以及全系统关键结构材料的设计和初步选型。研究结果表明,该系统反应堆可顺利达到临界且可满足10年以上的燃耗,流量分配后温度展平效果好,堆芯出口最大温度差91.08℃。热电转换效率为37.42%,剂量平面内的辐射剂量满足容许计限。

Orbital and planetary exploration missions require powerful,reliable,and durable energy,and space nuclear reactors are one of the highest energy densities for space propulsion.A conceptual design of a new megawattclass space nuclear power system is presented,with a fast neutron spectrum reactor with a power of 3.6 MW as the heat source,a helium xenon(He-Xe)gas mixture cooling the core,and a dual loop closed Brayton system with He-Xe as the working fluid for energy conversion.In addition,the structural design of key waste heat discharge equipment and the design and preliminary selection of key structural materials for the entire system were also carried out.The research results indicate that the reactor of this system can smoothly reach the critical point and meet a burnup of more than 10 years.After flow distribution,the temperature flattening effect is good,and the maximum temperature difference at the core outlet is 91.08℃.The thermoelectric conversion efficiency is 37.42%,and the radiation dose in the dose plane meets the allowable limit.