Hot channel factors for rod temperature calculations in LMFBR assemblies

Abstract

Abstract The methodology and philosophy of hot channel factors and the analytical procedure in their application to the core thermal-hydraulic design of LMFBRs are discussed. The hot channel factors adopted in the calculation of fuel and blanket rod temperatures for the Clinch River Breeder Reactor are quantitatively presented; the experimental data base of some of the hot channel factors used in determination of maximum cladding temperature are discussed in detail. Power-to-melt uncertainties, introduced for the first time during the CRBRP design to assess the margin-to-incipient melting in fuel and blanket rods, are presented and quantitatively elaborated. The role of the hot channel factors on the overall core thermal-hydraulic design and extension of uncertainty analyses to calculations other than rod temperature are discussed along with recommendations for improvements in hot channel factors analyses.