Influence of Accident-Tolerant Fuel With Steel Cladding for Sustainable Heat Transfer in the Reactor Core of VVER-1200

Abstract

Since the events at the Fukushima–Daiichi nuclear power plant, there has been increased interest in developing accident tolerant fuel (ATF) to avoid accidents for light water reactors where Uranium-Silicide-based fuel has an excellent field to minimize the hydrogen hazards. Similarly, steel cladding is at the center of attraction for researchers nowadays. In this research, the feasibility of using Uranium-Silicides (i.e., U3Si, U3Si2, and U3Si5) combined with different types of austenitic steel (i.e., AISI) was investigated to improve the safety performance. A three-dimensional (3D) computational fluid dynamics (CFD)-coded star ccm+ model was used to assess heat transfer performance in the hexagonal fuel assembly of a supercritical water-cooled reactor VVER-1200. Utilizing the computational environment of star ccm+, the test analysis was conducted for a portion of fuel height using the realizable K-Epsilon Two-Layer Wall turbulence model. This analysis showed that the combination of U3Si2 fuel with AISI-348 cladding got superiority over other ATF-AISI fuel-claddings assemblies to use in the reactor core of VVER-1200 because of their lower central fuel temperature value with good mechanical and thermal advantages. This work also derived an empirical heat transfer coefficient equation to guide the relevant future investigations on the thermal analysis of the core.