AP1000 Core Design Development for Higher Burn-up and Long Operational Cycle Length

Abstract High fuel burn-up and long cycle length are the main objectives for economic and reliable operation of Advanced Nuclear Power Reactors. The selected cladding material to stand for high burn-up and long cycle length is HANA-4 alloy. AP1000 core was developed through increasing the fuel enrichment to higher values than the initial values and replacing the ZIRLO cladding by HANA-4 cladding to achieve higher burn-up and longer cycle length. The initial core and the developed core were simulated using Monte Carlo N-Particle Transport Code MCNPX. The criticality control parameter, core cycle length and spent fuel radionuclides inventory were calculated. The results showed that the developed reactor core can reach a cycle length up to 22 months at fuel discharge burn-up 75GWD/MTU safely using HANA-4 cladding compared to the initial design core which can reach to 18 months cycle length at fuel discharge burn-up of 60 GWD/MTU.