Feasibility Study of the Hydride Fuels (UZrH and UThZrH) in the VVER-1000 Core

This article contains keywords on the hydride fuel as a new candidate to achieved higher power density in the current LWRs. More power density and lower operational temperature core are the major motivations to use hydride fuel instead of the current oxide fuel in the LWRs. In the current research, we have studied selected hydride fuels for the VVER-1000 core. A pitch optimization of the core delayed neutron fraction and prompt neutron lifetime; reactivity coefficients (fuel, moderator, and void) in the VVER-1000 core are investigated. Moreover, calculations for the fuel burn up and radionuclide inventory are carried out after one year of operational time. It is shown that the fuel cycle and discharge burn up are increased with hydride fuels.

The results showed that typical hydride fuel has useful properties such as higher excess reactivity, less initial U loading, and less Pu production. However, because of some disadvantages like positive moderator temperature coefficient and higher ¹³⁵Xe and ¹⁴⁹Sm build-up, more study is needed to use hydride fuel as an alternative fuel in LWRs.