Optimization of a Fuel Assembly for Supercritical Water-Cooled Reactor CSR1000

Fawen Zhu,Ti Yue,Quan-Yao Ren,Xiang Li,Lele Zheng,Hua Pang,Shan Huang,Linna Feng,Renjie Ran

doi:10.3389/fenrg.2021.678741

Abstract

As one of the Generation IV nuclear reactors, the SCWR (supercritical water-cooled reactor) has high economy and safety margin, good mechanical properties for its high thermal efficiency, and simplified structure design. As the key component of nuclear reactor, the fuel assembly has always been the main issue for the design of the SCWR. The design of the fuel assembly for CSR1000 proposed by the Nuclear Power Institute of China (NPIC) has been optimized and presented in this study, which is composed of four subassemblies welded by four filler strips and guide thimbles arranged close together in the cross-shaped passage. Aiming at improving the hydraulic buffer performance of the cruciform control rod, the scram time and terminal velocity of control rod assembly were calculated to assess the scram performance based on the computational fluid dynamics and dynamic mesh method, and the mechanical property and neutronic performance of assemblies were also investigated. It has been demonstrated that the optimized fuel assembly had good feasibility and performance, which was a promising design for CSR1000.

Highlights

The supercritical water-cooled reactor (SCWR) is one of the most promising reactors for Generation IV nuclear reactors due to its higher thermal efficiency and more simplified structure than the state-of-the-art LWRs
In China, a thermal spectrum SCWR concept called CSR1000 was proposed by the Nuclear Power Institute of China (NPIC) with a two-pass core arrangement, which increased the core heating length and decreased the temperature difference in the axial direction effectively (Xia et al, 2013)
The large impact load was attributed to the lack of hydraulic buffer effect when the cruciform control rod was inserted into the fuel assembly, which was a key design for the rod cluster control assemblies (RCCAs) in the pressurized water reactor (PWR)

Summary

INTRODUCTION

The supercritical water-cooled reactor (SCWR) is one of the most promising reactors for Generation IV nuclear reactors due to its higher thermal efficiency and more simplified structure than the state-of-the-art LWRs (light water reactors). In China, a thermal spectrum SCWR concept called CSR1000 was proposed by the Nuclear Power Institute of China (NPIC) with a two-pass core arrangement, which increased the core heating length and decreased the temperature difference in the axial direction effectively (Xia et al, 2013). Considering the two-pass core structure of CSR1000 and the separation of moderator water and coolant water, the new design of the 2 × 2 fuel assembly cluster consisting of four subassemblies was developed (Zhu et al, 2013). The large impact load was attributed to the lack of hydraulic buffer effect when the cruciform control rod was inserted into the fuel assembly, which was a key design for the rod cluster control assemblies (RCCAs) in the pressurized water reactor (PWR). Considering that the irradiation deformation of the cruciform control rod was much larger than that of the RCCA in the PWR, the gap between the cruciform control rod and the cross channel of the fuel assembly must be set as a reasonable value

Design parameter

CONCLUSION

DATA AVAILABILITY STATEMENT