超临界水冷堆中子能谱计算及安全性分析

超临界水堆是国际第Ⅳ代核能系统论坛推荐的六种第Ⅳ代核电反应堆堆型之一，与现有的轻水堆相比，具有热效率高、系统结构简单、造价低等优点。建立了MCNP程序下的超临界水堆堆芯物理计算模型，解决了燃料组件几何结构过于复杂精细难以建模的技术难题；考虑了堆芯轴向冷却剂密度的不均匀分布，计算并分析各区域的中子能谱分布；对失水事故下的超临界水冷堆安全性进行了分析，研究了不同区域冷却剂丢失程度对反应性及有效增殖系数的影响，表明所设计堆型具有较高的安全性；分析处理失水事故的应对措施，验证了使用注入硼水措施处理超临界水冷堆失水事故的可行性。

Neutron spectrum calculation and safety analysis for supercritical water-cooled reactor

The supercritical water reactor is one of the six reactors recommended by Generation IV International Forum. Compared with existing light water reactors, the supercritical water reactor has advantages of high thermal efficiency, simplified system structure and low cost. The physical model of the supercritical water reactor is established with MCNP program in this paper, which solves the problem of intricate geometry of fuel assembly. The change of coolant density along the axis is considered and the neutron spectrum distribution of different regions of the core is calculated. The safety in loss of coolant accident for the supercritical water reactor and the effect of missing coolant in different regions on the reactivity and effective multiplication factor analyzed. The results show the supercritical water reactor core has high security. The countermeasures of loss of coolant accident is studied and the effectiveness of boron water cooling is validated. The research not only provide important reference for the construction and security analysis of the supercritical water reactor, but also has great significance for the application and development of the supercritical water reactor.