Speaker
Description
TRR-1/M1 reserach reactor is loaded with 8.5% and 20% weight of uranium standard fuel elements. Fuel elements must periodically be shuffled to the reactor core in order to optimize the power, flux distribution and reactivity excess. The Reactivity Initiated Accident (RIA) analysis has been performed for rapidly removal sample from the reactor core and reactivity insertion rate of a sample is assumed to be $1.00/s. The objective of this study is to demonstrate that TRR-1/M1 could be operated safely for 1.3 MW power after shuffling with new core loading configurations containing these 20% weight fuel elements with high burn up in the B ring instead of 8.5% weight. The thermal–hydraulic parameters have been calculated to ensure that the safety margins are sufficient. Therefore, COOLOD-N2 and EUREKA-2/RR for TRR-1/M1 reactor was modelled for steady state and transient conditions coupled with MCNP transport code to calculate coolant and fuel temperature in the core and some parameters in the axial distribution of Departure from Nucleate Boiling Ratio (DNBR) for the hottest channel. The conclusion is that the high burnup 20% weight fuel elements located in B ring had no significant influence on the safety of the reactor. For RIA, the results shown that the negative temperature coefficient which is the negative feedback characteristics of TRIGA provided safety even at larger magnitudes of reactivity during reactor transients. The accident analysis shown that the fuel temperature increases only slightly since the transient is very short, therefore, insignificant energy produced during the accident to heat up the fuel. The maximum fuel temperature occurs for this study is below the safety limit for TRR-1/M1.
Keywords: reactor fuel, core loading, Reactivity Initiated Accident, transients
