Aluminum-Metal Fueled Long Life Fast Reactor Cores with Inherent Safety Features

摘要

A large fast reactor core with inherent safety features has been proposed by using ternary aluminum alloy (U-Pu-Al). The large thermal conductivity of aluminum alloy will provide good performances during reactor transients. The proposed core has shown inherent safety characteristics against both the Unprotected Loss of Flow (ULOF) events and the Unprotected Transient of Over-Power (UTOP) events due to a burn-up reactivity less than 1$ and a negative sodium void reactivity. In recent years a long life core concept has been focused for the fast reactor plants to meet the requirement of economic performances. In this study, we have assumed that the cycle length should be increased up to 4 years which corresponds to the ordinary fuel structure life time determined by neutron fluence. Since the burn-up reactivity generally increases in proportion to the cycle length, minor actinides are introduced to the fuel in order to suppress the increase in burn-up reactivity, while they may cause an increase in sodium void reactivity.