小型核热推进反应堆概念设计

Conceptual Design of a Small Reactor for Nuclear-powered Propulsion System

与化学推进相比,核热推进具有大推力、高比冲、长寿命、可重复启动等特点。本文基于核热推进飞行器的工作特点,通过综合考虑飞行器飞行性能和反应堆内传热性能,分析了反应堆半径、高度、冷却通道直径等设计参数对飞行器飞行性能的影响规律,探究了不同设计参数之间的影响规律,获得了满足热工设计准则的反应堆设计边界,阐明了燃料表面最高温度等热工设计准则对堆芯尺寸、推力和比冲的限制,探讨了设计参数对飞行器飞行性能的影响规律。通过综合考虑反应堆热工特性和飞行器飞行性能,本文提出了一种适用于核热推进系统的小型核反应堆概念设计。并利用蒙特卡罗程序OpenMC评估了该设计的中子学特性。模拟结果表明,该设计在控制棒插入和拔出条件下都满足临界要求,且控制棒的插入对于反应堆功率峰因子的影响较小。

Compared with the chemical propulsion,nuclear-powered propulsion has the advantages of high specific impulse,large thrust,long operating life and repeatable start-up.Based on the operating characteristics of the aircraft with nuclear-powered propulsion system,the influence of reactor design parameters such as radius,length,and diameter of coolant channel on the flight performance of the aircraft were studied by comprehensively considering the flight performance of the aircraft and the heat transfer performance in the reactor.With consideration of a maximum surface temperature of fuel,the limitations to geometry size,thrust and specific impulse are clarified respectively.By comprehensively considering the thermal-hydraulic and engine performance,a conceptual design of a small reactor suitable for nuclear-powered propulsion system is proposed.The Monte Carlo code OpenMC was used to evaluate the neutron characteristics of the design.It has been found that the criticality requirements are satisfied under both operating and shutdown conditions and the insertion of the control rod has small effect on the reactor peaking power factor.