Nuclear Techniques ›› 2020, Vol. 43 ›› Issue (5): 50602-050602.doi: 10.11889/j.0253-3219.2020.hjs.43.050602

• NUCLEAR ENERGY SCIENCE AND ENGINEERING • Previous Articles     Next Articles

Placement scheme of burnable poisons in a small modular fluoride-cooled high temperature reactor

Sijia LIU1,2,Guifeng ZHU1(),Rui YAN1,2,Yang ZOU1,2,Hongjie XU1,2()   

  1. 1.Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
    2.University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2019-12-18 Revised:2020-01-06 Online:2020-05-15 Published:2020-05-07
  • Contact: Guifeng ZHU,Hongjie XU;
  • About author:LIU Sijia, female, born in 1991, graduated from University of Science and Technology of China in 2013, doctoral student, focusing on reactor physics research
  • Supported by:
    Strategic Priority Research Program of Chinese Academy of Sciences(XDA02010000);Natural Science Foundation of Shanghai(19ZR1468000)

Abstract: Background

Small modular fluoride-cooled high temperature reactor (SM-FHR), with inherent safety and high temperature output ability, will accelerate the diversified development of world energy and meet the demand of comprehensive utilization of energy.


This study aims to simplify the reactivity control of SM-FHR, one of the key design goals, by using burnable poisons of boron carbide to lower the excess reactivity of SM-FHR.


Based on the SM-FHR design model, burnup code MOBAT was used to analyze the excess reactivity curves under different loads, different particle sizes and different space distribution of burnable poisons in fuel compacts.


Calculation results show that an optimal scheme exists when volume ratio of fuel to burnable poison (F/P) is 52, and particle size is 200 μm with lower loading in some outer assembles. Its excess reactivity is reduced from 38 000 ×10-5 to 2 500 ×10-5, and the power peak factor after layout of burnable poisons is only 1.26. The burnup time is decreased, but it still meets refueling cycle expectation for more than 2 full power years.


The layout scheme of burnable poisons proposed in this paper makes the core burnup depth and power distribution flattened, hence improving the core safety.

Key words: Small modular, TRISO, Molten salt reactor, Burnable poison, Burnup

CLC Number: 

  • TL3