Modification and validation of THEATRe code for the plate type fuel nuclear reactor

► Modification of THEATRe code is presented. ► The modification was done by inserting a computer program in the source library of THEATRe code. ► The verification studies were performed by comparing the results obtained from the modified THEATRe and RELAP5 codes. ► The verification studies were done by analyzing the thermal hydraulics of a small nuclear reactor core. ► The simulation results from both codes validate the applicability of THEATRe code for plate type fuel nuclear reactor.