Neutronic effect of utilizing TRIZO particles on core characteristics of experimental power reactor

Based on its superior characteristics and to provide core outlet temperature no less than 1000 °C for thermochemical hydrogen production, ZrC becomes a promising candidate to replace SiC coating layer of TRISO coated fuel particles. This paper aimed to study the neutronic effect of utilizing TRIZO coated fuel particles on core characteristics of experimental power reactor. A series of calculations were performed with MCNP6 code and ENDF/B-VII library. The calculation results show that replacement of SiC with ZrC will result in slightly decreased value in effective multiplication reactor (keff), slightly increased value in control rod worth and shutdown margin reactivity, and somewhat more negative value in temperature coefficient of reactivity. The effective delayed neutron fraction (βeff) in ZrC core presents lower values than in SiC core which cause a reduction in the ability to control the reactor. However, the reduced controllability via the lower βeff of ZrC core can be compensated by its favourable temperature coefficient and shutdown margin reactivity. These results conclude that replacing SiC with ZrC particles into experimental power reactor would have considerable impact and benefit from the viewpoint of reactor operational safety.