Development of Multidimensional Gap Conductance Model for Thermo-Mechanical Simulation of Light Water Reactor Fuel

경수로 핵연료 열-구조 연계 해석을 위한 다차원 간극 열전도도 모델 개발

  • Kim, Hyo Chan (LWR fuel technology division, Korea Atomic Energy Research Institute) ;
  • Yang, Yong Sik (LWR fuel technology division, Korea Atomic Energy Research Institute) ;
  • Koo, Yang Hyun (LWR fuel technology division, Korea Atomic Energy Research Institute)
  • 김효찬 (한국원자력연구원 경수로핵연료기술개발부) ;
  • 양용식 (한국원자력연구원 경수로핵연료기술개발부) ;
  • 구양현 (한국원자력연구원 경수로핵연료기술개발부)
  • Received : 2013.09.09
  • Accepted : 2013.12.05
  • Published : 2014.02.01


A light water reactor (LWR) fuel rod consists of zirconium alloy cladding tube and uranium dioxide pellets with a slight gap between them. The modeling of heat transfer across the gap between fuel pellets and the protective cladding is essential to understanding fuel behavior under irradiated conditions. Many researchers have been developing fuel performance codes based on finite element method (FE) to calculate temperature, stress and strain for multidimensional analysis. The gap conductance model for multi-dimension is difficult issue in terms of convergence and nonlinearity because gap conductance is function of gap thickness which depends on mechanical analysis at each iteration step. In this paper, virtual link gap element (VLG) has been proposed to resolve convergence issue and nonlinear characteristic of multidimensional gap conductance. In terms of calculation accuracy and convergence efficiency, the proposed VLG model has been evaluated for variable cases.


Light Water Reactor Fuel;Gap Conductance;Thermo-Mechanical Simulation;Finite Element Method


Grant : 핵연료 연소성능 평가기술개발

Supported by : 한국연구재단


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