Analysis of Manual Reactor Trip of NEK NPP in APROS Computer Code

The Slovenian Krško Nuclear Power Plant (NEK) model was built in using APROS - Advanced PROcess Simulation environment. basis for the this RELAP5/MOD3.3 Engineering Handbook, updated to 26th cycle and also includes upflow conversion modification. A detailed nodalisation created each system every separately validated. current covers primary circuit with core kinetics model, secondary their control systems. steady state of NEK already having been validated, plan now is validate some transients design accidents. In article plant behaviour after manual reactor trip analysed detail. Two scenarios transient are performed, where either Main Steam Isolation Valve (MSIV) closes 60s – case A, or remains open B. After from 100% power, signal actuations times were followed then responses different affected systems being observed. All those recorded values compared identical performed on similar code. This procedure allowed bring one step forward towards assured have accurate calculations.