As part of an I-NERI project to develop safety analysis codes and experimental validation for a VeryHigh Temperature Gas-Cooled Reactor (VHTGR), we have developed MCNP5 [1] models to represent material heterogeneities inherent in the microsphere fuel particles and fuel compacts for a GT-MHR design [2]. We have also performed preliminary coupled nuclear-thermalhydraulic (NTH) analysis to obtain ...

Validation of EOPs (Emergency Operating Procedures) and FRGs (Function Restoration Guidelines) can be achieved either through plant full scope simulator or on desk top exercises. The exercise is conducted when for the given scenario not suitable. In verification cases predefined should evaluated possible branching foreseen. presented LOHS, with bleed feed procedure initiated. Best estimate ligh...

Recently, several advanced multidimensional computational tools for simulating reactor system behavior during real and hypothetical transient scenarios were developed. One of such advanced, best-estimate systems codes is TRAC/RELAP Advanced Computational Engine (TRACE), developed by the U.S. Nuclear Regulatory Commission. The TRACE comes with a graphical user interface called SNAP (Symbolic Ana...

As a part of the TEPSS project, within the last fourth Framework Programme of the European Union R&D activities, an investigation focused on the residual heat removal passive safety systems in the future boiling water reactors was performed using PANDA facility and the codes RELAP5, MELCOR and TRAC-BF l. The main purpose was to ensure the capacity of these passive safety systems under a wide ra...

This report has been prepared as a part of the Agreement on Research Participation and Technical Exchange under the International Code Application and Maintenance Program. KS-i Test 35-1 data on the behaviour of the heated rod temperatures in the partially uncovered VVER Core model were simulated with RELAP5/MOD3.2 to assess the code, especially its non equilibrium (unequal phase temperatures) ...