Thermal-Hydraulic Analysis of Fuel Subassemblies for Sodium-Cooled Fast Reactor

Thermal-hydraulic analysis of fuel subassemblies for the sodium-cooled fast reactor is important in respecting design limits while achieving higher outlet temperature， and it is essential to predict, reliably and accurately, the coolant temperature distribution in individual fuel subassembly. Based on F.C.Engel’s work and CRT model, three semiempirical correlations ICRT were developed to calculate laminar, transition, and turbulent parallel flow pressure drop across wire-wrapped rods. With CRT model and the heat transfer coefficient WEST, reasonably accurate temperature distribution in a fuel subassembly was obtained by the improved subchannel analysis code SUPERENERGY. The results indicate lower coolant temperature and higher film temperature in internal regions. The code CFX was used to show the 3D flow field and temperature distribution in a rod bundle, and the numerical results show good agreement with CRT model, ICRT correlation and the improved SUPERENERGY code.