The Study on the Effect of Core Neutron Parameters on the Maximum Linear Power Density During Condition II PCI Transients

PCI (Pellet-Cladding Interaction) involves the interaction between fuel pellet and cladding. PCI analysis is based on realistic assumptions aimed at evaluating the risk of PCI occurrence in fuel rods during severe Condition II PCI transients. The maximum linear power density during transients directly affects the PCI margin. This study takes the CPR1000 unit as the research object and analyzes the impact of main core neutron parameters on the maximum linear power density during Condition II PCI transients. The study shows that the prompt neutron lifetime has no effect on transient linear power density, while the delayed neutron fraction, boron concentration, and Doppler power coefficient have a significant impact on the maximum linear power density during transients. It is challenging to establish a direct relationship between neutron parameters and maximum linear power density for Condition II PCI transients.