Neutronic Analysis of SiC/SiC Sandwich Cladding Design in APR-1400 under Normal Operation Conditions

• Published in: Energies (Basel) Vol. 15; no. 14; p. 5204
• Main Authors: Alaleeli, Maithah, Alameri, Saeed, Alrwashdeh, Mohammad
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.07.2022
• Subjects: accident-tolerant fuels; Alloys; Claddings; Design; Electric power distribution; Investigations; light water reactor; Linings; neutronics; Niobium; nuclear fuel; Nuclear power plants; Nuclear reactors; Physics; Pressurized water reactors; Reactor physics; Reactors; Silicon carbide; Tantalum; Tightness
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en15145204

Our aim is to study the neutronic behaviour of potential accident-tolerant fuel (ATF) claddings in a pressurised water reactor under normal operations. This work compares ATF silicon carbide composite (SiC/SiC) cladding to conventional ZIRLOTM cladding in APR-1400. Additionally, a “sandwich” cladding design developed by the CEA is used for SiC/SiC. The design structure includes a liner in between two layers of the composite to ensure leak tightness. The two proposed liners are Niobium (Nb) and Tantalum (Ta). Serpent 2, a Monte Carlo reactor physics lattice code, is employed to model both cladding materials in APR-1400 at three different levels: pin cell, fuel assembly, and core. The criticality, neutron spectrum, actinide inventory, and power distribution as a function of burnup are investigated. The simulations show that SiC/SiC with the Nb liner displays a far superior performance than the Ta liner across all examined characteristics. Ta leads to a harder neutron spectrum and increased Pu-239 content throughout the cycle, while Nb presents negligible effects. In fact, SiC/SiC with the Nb liner performs very similarly to ZIRLOTM at all model levels. The results indicate that, in terms of neutronics, the adoption of the SiC/SiC composite would entail little to no changes to current APR-1400 operations.