Effect of Neutronic Parameters on the Cladding of the AP1000 MOX Fuel by Calculations Using MCNP Code

Abstract

The current work investigates the impact of MOX fuel introduction on AP1000 neutronic characteristics. The MCNP code with new silicon carbide cladding and the AP1000 core with three 235U enrichment zones (2.35%, 3.40%, and 4.45%) were used to perform the neutronic computations. The outcomes demonstrated that the simulated model for the AP1000 core complies with the optimization requirements as a Westing-house reference. The results which included: effective multiplication factor, keff, and excess reactivity were calculated and compared with the available published results. The keff in the cold zero power was found to be AP1000 Zircaloy, SiC, FeCrAl, and SS-310 cladding are (1.20685+/-0.00028), (1.21170+/-0.00028), (1.14435+/-0.00027), and (1.12432+/-0.00028). The excess reactivity is 17.11%, 17.47% 12,61%, and 11.06% with the MOX fuels, respectively. These numbers line up with the keff value of 1.205 given in the AP1000 Design Control Document for the UO2 fuel core. However, the results are positive and support the AP1000 reactor core's design and efficient modeling as being safe operation.