ANALYSIS ON HEAT TRANSFER PERFORMANCE SUB-CHANNELS OF SODIUM-COOLED FAST REACTOR FUEL ASSEMBLIES BASED ON ENTRANSY

In this pa per, the sym met ric heat trans fer per for mance of so dium-cooled fast re ac tor fuel as sem blies was an a lyzed and stud ied. The model is an a lyt i cally op ti mized based on sub-chan nel calculations. The deviations of the numerical simulation results from the pre-existing experimen tal data in the lit er a ture are within 10 %, with an av er age de vi a tion of 2.5 %, which tested the re li abil ity of the model. The cal cu lated re sults dem on strated that the dis tri bu tion of the axial power, temperature, and coolant of the reactor core is approximately symmetric M-shape. The re ac tor core cool ant has a monotonic in crease in ax ial dis tri bu tion with the clad ding tem per a ture and the tem per a ture peaks all ap pear at the re ac tor core out let. The in dividual fuel assemblies' internal temperature is relatively sensitive to the axial power distribu tion, and there are troughs around the im ports and ex ports. The sim u lated re sults showed that the cen ter tem per a ture of the hot test rod re ac tor core block reached 965.65 K. This pa per pro vides a better guide to un der stand ing the over all heat trans fer ef fect by op ti miz ing the heat trans fer model.