Nuclear Techniques ›› 2014, Vol. 37 ›› Issue (03): 30603-030603.doi: 10.11889/j.0253-3219.2014.hjs.37.030603

• NUCLEAR ENERGY SCIENCE AND ENGINEERING • Previous Articles     Next Articles

Study of fluid fuel influence on delayed neutron in Molten Salt Reactor

CAI Jun1,2 XIA Xiaobin1 CHEN Kun1 MEI Mudan1   

  1. 1(Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jiading Campus, Shanghai 201800, China) 2(University of Chinese Academy of Sciences, Beijing 100049, China)
  • Received:2013-10-17 Revised:2014-01-11 Online:2014-03-10 Published:2014-03-14

Abstract:

Background: The Molten Salt Reactor (MSR) is one of the six advanced reactor types for future nuclear energy systems in the Generation IV International Forum (GIF), possessing the advantages of good neutron economics, inherent safety, processing online, nuclear nonproliferation, etc. Due to the fluid fuel, a part of delayed neutron precursors drifts out of the reactor and decays in the loop, which is different from the solid-fuel reactor. Purpose: The distribution of delayed neutrons with different fuel velocity for Molten Salt Reactor Experiment (MSRE) is analyzed to provide reference for safety design of MSR. Methods: Based on the neutron kinetics and approximate method of homogeneous reactor, a distribution model of delayed neutron was presented. This model is applied to the distribution study of delayed neutrons with different fuel velocity. Results: The number of delayed neutrons in a core radius of 20 cm was more than that in a core radius of 30 cm. When the flow velocity of fuel decreased by a half, the discrepancy of delayed neutrons between the fifth-group and sixth-group precursors is within 6%. Conclusion: The number of delayed neutrons is increasing toward the center of reactor core. The group of delayed neutron precursors with shorter half-time has little effect on the flow velocity of molten salt.

Key words: Molten Salt Reactor Experiment (MSRE), Delayed neutrons precursors, Fluid fuel