RELAP5程序应用于二次侧非能动余热排出系统设计的初步评价

Preliminary Evaluation of RELAP5 for Design of Secondary Side Passive Residual Heat Removal System

应用实验数据对RELAP5/MOD3.3程序应用于二次侧非能动余热排出系统设计进行初步评价,结果表明,系统投入初期,由于RELAP5程序的一维流动假设,针对事故冷却水池早期的内部三维对流传热模拟存在不足;系统投入后期,冷却水池内部传热为泡核沸腾,池式沸腾换热占主导地位,程序计算结果与实验结果较吻合,RELAP5/MOD3.3程序基本适用于二次侧非能动余热排出系统的稳态运行特性分析。

In this paper, preliminary evaluation of RELAP5 code was made on its application to the design of second side passive residual heat removal system（PRHR） by comparing to the experimental data. Because the theoretical basis of RELAP5 code was one-dimensional flow hypothesis, RELAP5 code was inadequate in the simulation of natural convection heat transfer in accident cooling pool during the initial stage of PRHR. In later-period of PRHR, the heat transfer mode in accident cooling pool was nucleate boiling based, and pool boiling had absolute predominance in the heat transfer quality, and the calculation results fitted the experimental data quite well. RELAP5 code can be basically applied to the steady state performance analysis of second side passive residual heat removal system.