基于蒙特卡罗和CFD耦合模拟的空间锂冷核反应堆设计分析

Analysis of a Space Lithium-Cooled Nuclear Reactor Design with Coupling Monte Carlo and CFD Simulation

为了满足未来深空探测的需求,中科院核能安全技术研究所提出5.2 MWt轻量化的空间锂冷核反应堆初步设计方案。该方案采用一体化式堆芯设计、非均匀锂冷却剂流道,以及由硼粉和控制棒组成的控制系统。在SuperMC多物理耦合框架下,基于随机逼近耦合求解策略,通过蒙特卡罗中子输运和计算流体力学CFD耦合的高保真耦合模拟方法对该空间堆设计进行模拟分析。耦合模拟结果显示,该空间堆设计满足反应性要求,非均匀流道设计可以使径向功率分布更均匀,在正常运行工况下,各材料的温度均低于限值,仿真模拟结果也为空间堆设计提供了优化思路。

In order to satisfy the demand of megawatt-class and lightweight for future deep space exploration,the Institute of Nuclear Energy Safety Technology proposed the preliminary design for a 5.2 MWt space lithium-cooled nuclear reactor.The reactor design has many unique features,such as the integrated fuel,the non-uniform lithium flow channels,and the control system consisting of boron powder and control rods that can compensate reactivity by emptying the boron powder with the reactor operation.For a new type of space nuclear reactor design like this,there is little design experience.The preliminary design of the reactor needs to be verified and optimized with high fidelity simulation,which can be carried out with the coupled Monte Carlo and computational fluid dynamics(CFD)simulation.In this contribution,the coupling neutronics and thermal performance of the reactor design was evaluated.The coupling results show that the reactivity requirements of the reactor design can be satisfied.The non-uniform flow channels flatten the power distribution,and the temperature of each material is lower than the limit under normal operating condition.The design of the model basically meets the requirements,and the coupling results also provide optimization ideas for the design.