Sensitivity study of core characteristic parameter of ATF loaded APR1400 core and cycle length compensation by enrichment adjustment

•This paper investigates the core characteristics of a reactor loaded with ATF.•Cr-coated and LAS doped fuel pellet ATF were considered.•The overall impact on core performance is not significant exculding cycle length. Following the Fukushima Daiichi accident, efforts have been made in a variety of disciplines to respond to nuclear accidents. From the perspective of nuclear fuel, various approaches have been attempted, and development has been made as an Accident Tolerant Fuel (ATF). Advanced fuel technology, often known as advanced fuel concepts, is ATF. The ATF is a type of fuel designed to be more resistant to damage in the event of a loss-of-coolant accident (LOCA) or other type of incident. Some ATF designs make use of materials that can better withstand high temperatures and pressures, which can help prevent fuel melting and release of radioactive materials. Currently, we are in the stage of developing a method to apply Cr coating on zircaloy cladding or a new cladding made of SiC. Additionally, some minerals like Cr, Mn, or La2O3-Al2O3-SiO2 (LAS) are doped into pellet materials to alter their characteristics in order to create ATF fuel. In this paper, the characteristics of a core loaded with Cr-coated clad, and LAS doped fuel pellet ATF was investigated. The multiplication factor, power distribution, peaking factor, moderator temperature coefficient, and cycle length of the ATF-loaded core were calculated and compared to the results of the ATF-free core. The neutron absorption increases when the ATF is loaded due to the Cr coating and LAS doped fuel pellet, resulting in a difference when compared to the reference case. However, this study confirmed that the difference attributable to ATF was not significant except for the cycle length. To compensate for the reduced cycle length due to ATF, the cycle length and peaking factor were evaluated for the core with increased fuel enrichment and compared with the results of the conventional core.