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Study on inherent neutron sources in MSR

  • Rui-Min Ji
  • Cheng-Gang Yu
  • Ming-Hai Li
  • Rui Yan
  • Yang Zou
  • Gui-Min Liu
Article
  • 36 Downloads

Abstract

The molten salt reactor (MSR) has received much recent attention. The presence of beryllium and the mixing of actinides with light nuclei in the fuel salt result in a relatively strong neutron source that can affect the surveillance at subcritical and transient characteristics during operation. In this study, we predict the inherent neutron sources based on a MSR model. The calculation shows that in the fresh core, the inherent neutron sources are mainly from alpha-induced neutrons. After power operation, the inherent neutron sources become remarkably stronger due to photoneutrons. Although being an insignificant part in the total neutron population during operation, the inherent neutron sources can be used as the installed neutron source after shutdown. If the MSR has continuously operated at full power (2 MWt) for 10 days, then there would be no need for the installed source within 80 days after shutdown. After operating constantly for 500 days, the installed neutron source can be eliminated within 2 years after shutdown.

Keywords

MSR Fuel salt Inherent neutron source Photoneutron Alpha-induced neutron 

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Copyright information

© Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Chinese Nuclear Society, Science Press China and Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Shanghai Institute of Applied Physics, Chinese Academy of SciencesShanghaiChina
  2. 2.University of Chinese Academy of SciencesBeijingChina

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