Simulation of the AP1000 reactor containment pressurization during loss of coolant accident

Abstract

The analysis of accidents in reactors is one of the most important parts of safety analyses in power plants. So many models have been simulated for survey of LOCA in containment of a reactor. Containment is the last barrier of safety in a reactor and LOCA can imposes the danger of destroying its integrity. Then simulations in this region of researches are too considerable. AP1000 has powerful safety related systems; therefore analysis of safety concepts on them is so important. One of the most important safety features of AP1000 is its passivity. This advantage provides many simplifications to enhance safety, reliability, construction, operation, maintenance, investment protection and plant costs. AP1000 containment is divided into several different sections in one of which the break of the primary system may happen. Analytical model has been developed by which the local pressure build up is calculated, taking into account the subdivision of the containment, resistances which prevent the free exchange of mass and energy between the subsections, and the location of the primary system break. The model is based on mass, energy, and momentum equations applied for each subsection. The energy source strength at the location of the break is based on appropriate two phase flow models.