Investigations on justification and development of concept of directsteam NPP with water cooled reactor at supercritical parameters with fast resonance spectrum
The features of experimental reactor WWER-SCD-30 cooled by water of supercritical parameters (Р = 25 МPа, t = 540 °С), with power of 30 MWt are considered. This reactor is characterized by fast resonance neutron spectrum and twopass coolant flow scheme. Physical characteristics of WWER-SCD-30 calculated for three types of fuel are given. The first of them is based on UO2 with ~ 20 % enrichment. The two other fuel types are from depleted uranium enriched by weapon or commercial plutonium. Application of small fuel assemblies without sheath that consist of ~ 19 fuel pins in each is provided. Calculated data on fuel cycles with these fuel types including values of Kef and maximum power density distribution form factor Kq – on fuel assembly and KV – throughout the reactor core volume in dependence of burning up duration are presented. The heat removal scheme of NPP with WWER-SCD-30 reactor is discussed. The maximum temperature on the fuel pin cladding is not higher than 620 °С.