溶液堆气泡及瞬态中子学模型

摘要

Fuel of aqueous homogeneous reactor (AHR) is in liquid state and serves as both fuel and moderator . Radiolytic gas bubbles are generated by collision between water molecules and fission fragments .Bubbles' existence and movement in the fuel make AHR's transient neutronics simulation difficult .In this paper ,a coupled neutron-ics and thermal-hydraulics method was introduced to recognize gas bubbles' behavior ;then a simplified gas bubbles model w as established to make an effective simulation of gas bubbles distribution;finally the simplified model was applied to transient neutronics model of AHRs .The results show that the gas bubbles' behavior accords with simula-ted results of coupling .%溶液堆的燃料(UO2(NO3)2水溶液)具有液体形态,兼作核燃料和慢化剂,裂变碎片与水分子碰撞产生辐照裂解气体气泡,气泡在燃料中存在和运动使得溶液堆的瞬态中子学模拟十分困难.本研究首先基于稳态的物理热工耦合方法对溶液堆进行模拟,对模拟结果体现的气泡行为特征进行提炼,建立溶液堆气泡数值模型,再将该气泡模型应用于溶液堆瞬态中子学分析程序中,使用该程序对瞬态试验进行模拟并与测量结果进行比较,发现气泡行为特征与耦合方法的模拟结果一致.