Development of a 3D thermohydraulic-neutronic coupling model for accident analysis in research miniature neutron source reactor (MNSR)

  • Ahmadi, M. (Department of Nuclear Engineering, School of Mechanical Engineering, Shiraz University) ;
  • Rabiee, A. (Department of Nuclear Engineering, School of Mechanical Engineering, Shiraz University) ;
  • Pirouzmand, A. (Department of Nuclear Engineering, School of Mechanical Engineering, Shiraz University)
  • Received : 2018.11.30
  • Accepted : 2019.05.27
  • Published : 2019.10.25


To accurately analyze the accidents in nuclear reactors, a thermohydraulic-neutronic coupling calculation is required to solve fluid dynamics and nuclear reactor kinetics equations in fine cells simultaneously and evaluate the local effects of neutronic and thermohydraulic parameters on each other. In the present study, a 3D thermohydraulic-neutronic coupling model is developed, validated and then applied for Isfahan MNSR (Miniature Neutron Source reactor) safety analysis. The proposed model is developed using FLUENT software and user defined functions (UDF) are applied to simulate the neutronic behavior of MNSR. The validation of the proposed model is first evaluated using 1mk reactivity insertion experiment into Isfahan MNSR core. Then, the developed coupling code is applied for a design basis accident (DBA) scenario analysis with the insertion of maximum allowed cold core reactivity of 4 mk. The results show that the proposed model is able to predict the behavior of the reactor core under normal and accident conditions with a good accuracy.


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