小型模块化钠冷快堆非能动余热排出系统分析研究

针对小型钠冷快堆模块化设计需求，提出了一种利用安全壳内空气自然循环将堆芯余热导入大气最终热阱的非能动余热排出系统方案。通过理论计算并结合系统分析程序RELAP5，对非能动余热排出系统进行建模，分析系统方案的可行性。结果显示：保守假设条件下，在钠装载量为2000 kg工况时，非能动余热排出系统功率在16.88 kW以上可保证堆芯燃料温度不超过安全限值。RELAP5计算结果表明，本文提出的非能动余热排出系统方案冷却功率大于所需最小功率，能满足小型钠冷快堆设计需求。

Design and Analysis of Passive Decay Heat Removal System for Sodium-cooled Small Modular Reactor

In order to meet the modular design requirements of sodium-cooled small modular reactor, a passive decay heat removal system solution based on natural circulation of air within the containment was proposed. Through theoretical calculation and system analysis program RELAP5, the passive decay heat removal system was modeled and the feasibility of the system scheme was analyzed. The results show that under the conservative assumption, when the sodium loading is 2000 kg, the temperature of core fuel will not exceed the safety limits when the thermal power of passive decay heat removal system is more than 16.88 kW. The calculation results of RELAP5 show that the cooling power of the passive decay heat removal system is larger than the minimum power required, and can meet the design requirements of sodium-cooled small modular reactor.