Innovative designed fuel pin of conceptual semi-heavy water research reactor with improved reactor safety

摘要

Improving thermal hydraulic parameters such as axial power distribution and decrease maximum fuel temperatures lead to higher reactor safety. In this study, with the variation of fuel pellet central hole (1UTVS) volume along the fuel pin axis, have achieved improvements of thermal hydraulic parameters of the semi-heavy water research reactor. The new design of fuel pin has contain fuel pellets with different radii central hole along the fuel pin axis. Calculations with the new design of fuel pin are carried out by coupling of neutronic (WIMSD5+CITATION) and thermal hydraulic (COBRA-EN) codes for a conceptual high neutron flux semi-heavy water research reactor. As a result, the axial Power Peaking Factor (PPF) decreased from 1.2827 to 1.2118 and minimum Departure from Nucleate Boiling Ratio (DNBR) has increased from 5.31 to 5.583. Maximum fuel temperature is decreased from 1595 to 1499.6 degrees C and core average thermal flux is increased from 1.1607 x 10(14) to 1.2447 x 10(14) n/cm(2).s at the Beginning of Cycle (BOC). These improvement which are the consequence of applying the new innovative design of the fuel pin lead to higher safety. This new idea of designed fuel pin with different radii central hole fuel pellets along the fuel pin axis can be used for nuclear reactors in order to improve their safety.