Study on the Movement and Deposition of Particles in Supercritical Water Natural Circulation Based on Grey Correlation Theory

Liangyu Zhu,Tao Zhou,Xijia Ding,Jialei Zhang,Xuemeng Qin

doi:10.3390/en12122315

Abstract

The movement and deposition of particles that occur during their natural circulation in supercritical water exercise an important impact on the safe and stable operation of a supercritical water reactor (SCWR). When supercritical water flows in pipelines, a large number of corrosive particles may be generated due to pipeline corrosion or the purity of the fluid itself. The presence of particulate matter affects the heat transfer efficiency of the pipeline, increasing flow resistance and easily promoting heat transfer deterioration. ANSYS-CFX numerical analysis software was used to simulate the natural circulation loop of supercritical water, and micron particles were added in the initial flow field. The effects of heating power, particle concentration and particle diameter on particle deposition were obtained. Through this analysis, it can be concluded that the heating of the pipeline has a certain inhibitory effect on the deposition of particles. The rise in both initial particle concentration and particle diameter serve to reinforce the deposition of particles in the heating section. Depending on the degree of influence, the contributory parameters to particle deposition include particle diameter, particle concentration and heating power in turn.

Highlights

Supercritical Water Reactor (SCWR) is the only water reactor among the six types of fourth generation reactors selected in the world, which has high power generation efficiency, thermal efficiency, economy and safety
Natural circulation is an important part of the passive safety system in supercritical water reactor (SCWR), which relies on the density difference between hot and cold sections to drive fluid flow and discharge waste heat
This paper mainly studies and analyzes the natural circulation in supercritical water reactors

Summary

Introduction

Supercritical Water Reactor (SCWR) is the only water reactor among the six types of fourth generation reactors selected in the world, which has high power generation efficiency, thermal efficiency, economy and safety. Natural circulation is an important part of the passive safety system in SCWR, which relies on the density difference between hot and cold sections to drive fluid flow and discharge waste heat. When supercritical water flows in pipelines, a large number of corrosive particles may be generated due to pipeline corrosion or the purity of the fluid itself. When corrosive particles accumulate to a certain extent in the wall, there is a difference in thermal expansion between the inner wall surface and the outer oxide layer, resulting in the fact that the inner wall of the pipeline will begin to peel off, seriously affecting the safe and stable operation for the reactor. This paper mainly studies and analyzes the natural circulation in supercritical water reactors. Keigo Karakama et al [1] used a direct

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Conclusion