RELAP5程序再淹没现象物理模型的敏感性分析

Sensitivity Analysis of Physical Models of Reflood through RELAP5

为了加深对再淹没现象的理解和对主流系统程序进行改进,对德国的FEBA台架试验用RELAP5/MOD3.2程序建模计算并与实验数据比较。结果表明:包壳温度的计算值明显低于实验结果,计算所得的再淹没开始时间也早于实验值。对与再淹没现象有关的重要物理模型参数进行敏感性分析表明:气泡液滴的相间摩擦系数、弥散流的相界面对气相的传热系数、壁面对液相的摩擦系数、膜态沸腾壁面对气相和液相的传热系数以及相界面的最小液滴直径等参数对计算结果的影响较大,后续工作可以对这些参数及其所在模型做重点研究。

In order to achieve better understanding of reflood phenomenon and make improvement on the mainstream system code,this paper use RELAP5/MOD3.2 code to simulate the FEBA(Flooding Experiments with Blocked Arrays) facility from Germany.firstly,the calculation is compared with the experiment data.results show that both the peak cladding temperature and the bundle quenched time are under predicted.Then sensitivity analysis is done to the important physical model parameters related to the reflood phenomenon.The results prove that the interfacial friction of bubbles and droplets,heat coefficient between gas and interface of dispersed flow,wall to liquid drag coefficient,heat transfer of film boiling flow regime and the minimum droplet diameter are parameters with relatively large influence.More efforts should be made on the research of these parameters and models in the next step of work.