非能动余热排出系统的瞬态特性数值分析

对用于新型压水堆非能动余热排出系统的热工水力特性进行了理论分析．该系统利用3个相互耦合回路的自然循环把停堆后的堆芯余热排出．在一维质量、动量和能量守恒方程的基础上建立了非能动余热排出系统的数学模型，并编制程序对模型进行了数值求解，模拟了非能动余热排出系统的瞬态特性．计算分析了冷热芯位差和余热交换器换热面积对系统特性的影响．结果表明，各参数的变化趋势是合理的．冷热芯位差和余热交换器换热面积越大，对系统越有利．

Numerical Study on Transient Characteristics of Passive Residual Heat Removal System

A theoretical investigation was performed on the thermal hydraulic characteristics of a passive residual heat removal system (PRHRS) for a new type of pressurized water reactor(PWR).Three-interknit natural circulation loops were adopted by this PRHRS to remove the residual heat of the reactor core.Based on the one-dimensional model and a calculation code,the transient characteristics of the PRHRS were studied in detail.Through the calculation analysis,it is found that the calculated parameter variation trends are reasonable.The higher height difference between the steam generator and the residual heat exchanger,and the larger heat transfer area of the residual heat exchanger are favorable to the passive residual heat removal system.