Fast Reactor Coolant Flow Field Temperature Field In A Single Box Of Fuel Components And Computing Research

On the design of fuel subassembly of sodium cooled fast reactor, the wire-spacing method is predominantly adopted. It' s essential to accurately predict the thermal-hydraulics behavior. The most important purpose of a thermal-hydraulics model is to describe the flow field and temperature field in a fuel subassembly. In the interior region of the subassembly, the flow mixing through the gaps between fuel rods results from turbulent flow exchange, sweeping crossflow and pressure-induced crossflow. In the peripheral region, a transverse flow called "a swirl flow" runs parallel with the duct wall.The purpose of this paper is to describe the thermal-hydraulics behavior of the coolant in rod bundles, especially the flow field and the temperature field. The main emphasis is on aspects of velocity distribution, temperature profile and pressure drop in the subchannels.Based on F. C. Engel's work and the CRT model, three semiempirical formulas have been developed for calculating the laminar, transition, and turbulent parallel flow pressure drop across rod bundles.Novendstern model, Russian formula and CRT model all can approximately predict the flow velocity distribution in subchannels, CRT model is the best. And West formula can accurately calculate convection heat transfer coefficient. Based on these, reasonably accurate temperature distribution can be computed by the improved SUPERENERGY code.The code CFX is used to show the flow field and temperature field in a rod bundle. The target of this work is to determine the detailed coolant velocity and temperature profile around the entire rod circumference in rod bundles as well as the detailed radial and circumferential temperature profile in the rod.Overall, a more realistic core thermofluids design is possible by implementing the study presented here.