Numerical study on the thermal-hydraulic safety of the fuel assembly in the Mast assembly

수치해석을 이용한 마스트집합체 내 핵연료 집합체의 열수력적 안전성 연구

Kim, YoungSoo;Yun, ByongJo;Kim, HuiYung;Jeon, JaeYeong

  • Received : 2015.01.20
  • Accepted : 2015.03.17
  • Published : 2015.03.31


In this study, we conducted study on the confirmation of thermal-hydraulic safety for Mast assembly with Computational Fluid Dynamics(CFD) analysis. Before performing the natural convection analysis for the Mast assembly by using CFD code, we validated the CFD code against two benchmark natural convection data for the evaluation of turbulence models and confirmation of its applicability to the natural convection flow. From the first benchmark test which was performed by Betts et al. in the simple rectangular channel, we selected standard k-omega turbulence model for natural convection. And then, calculation performance of CFD code was also investigated in the sub-channel of rod bundle by comparing with PNL(Pacific Northwest Laboratory) experimental data and prediction results by MATRA and Fluent 12.0 which were performed by Kwon et al.. Finally, we performed main natural convection analysis for fuel assembly inside the Mast assembly by using validated turbulence model. From the calculation, we observed stable natural circulation flow between the mast assembly and pool side and evaluated the thermal-hydraulic safety by calculating the departure from nucleate boiling ratio.


Mast assembly;Fuel assembly;Computational Fluid Dynamics;Natural convection;Departure from Nucleate Boiling Ratio(DNBR)


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Supported by : 한국연구재단