铅基反应堆自然循环与应急余热排出研究

自然循环特性是铅基反应堆一回路的关键运行特性,对反应堆的非能动应急余热排出具有重要的影响,自然循环特性与余热排出能力是反应堆热工水力研究的重要内容。采用多孔介质方法,建立了CiADS铅基堆1/4三维计算模型,使用FLUENT程序对额定工况与低功率工况进行稳态计算。为了研究全厂断电事故下的余热排出过程,从热工水力的等效原则出发,尝试建立二维等效模型以提高瞬态计算效率。结果表明,CiADS铅基堆具备低功率自然循环运行能力和一定的事故容错能力;二维等效模型与三维模型计算结果吻合较好,可用于瞬态下的简化分析;CiADS铅基堆的非能动余热排出系统能够较好地应对全厂断电事故,反应堆具有良好的固有安全性。

Study on Natural Circulation and Residual Heat Removal Capability of the Lead-based Fast Reactor

The natural circulation characteristics is the key operating characteristic of the primary circuit of the lead-based reactor, which has an important influence on the passive residual heat removal system of the reactor. The natural circulation characteristics and residual heat removal capacity in the reactor are an important part of the thermal hydraulic research of reactor. Using the porous media method, the 1/4 3D calculation model of the CiADS lead-based reactor was established, and the steady state calculation of rated conditions and low power operating condition were performed by FLUENT code. In order to study the transient process of residual heat removal of CiADS lead-based reactor under the station blackout accident, a 2D equivalent model which according to the principles of thermal hydraulic equivalence was established for transient calculation. The results show that CiADS lead-based reactor has low power natural circulation operation capability and a certain degree of accident tolerance; The results of 2D equivalent model and 3D model agree well with each other and the 2D model can be used in transient analysis; The 2D transient calculation results show that the passive residual heat removal system can cope well with the station blackout accident, and the CiADS lead-based reactor has good passive safety performance.