MELCOR与SPEEDI程序在放射性物质释放量评估中的应用比较

轻水堆核电厂严重事故发生时,公众及核电厂工作人员最为关心的就是放射性物质的泄漏,如何准确地评估放射性物质的释放水平,对指导核电厂工作人员采取相关的应急措施具有重要的意义。目前,用于实时评估核事故情况下放射性物质释放量的方法主要有两类:(1)基于核电厂事故工况分析的评估方法,如MELCOR程序;(2)根据辐射环境监测数据反演的评估方法,如SPEEDI程序。前者主要以程序模拟计算为主,后者主要是基于核电厂周围辐射环境监测的数据,具有实时性。本文通过对MELCOR和SPEEDI这两类评估程序在福岛核事故中的应用比较,阐述两类评估方法在评估放射性物质释放量时发挥的效用。

The Contrast of MELCOR and SPEEDI Codes in Evaluating the Radioactive Material Release Amount in a Serious Nuclear Accident at Light Water Reactor

When a nuclear accident occurs in a nuclear power plant（NPP）,the most attention for the public and the plant operators is about the release amount of the radioactive materials from the NPP.How to evaluate the release amount more accurately is significant for the plant operators,because the evaluation directs their emergency acts.At present,two kinds of methods are mainly used for the evaluation of the radioactive material release amount in an accident.One method is the evaluation based on plant behavior analysis,such as MELCOR code,and the other one is based on inverse estimation using environmental monitoring data,such as SPEEDI code.The first method needs the specific situation of the NPP,and the second is the method with real - time capability.With contrasting two codes,MELCOR and SPEEDI, which have been used in the Fukushima accident,the efficiency of the two codes in evaluating the release amount of the radioactive materials is elaborated.