Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Numerical Analyses to Simulate Thermal Stratification Phenomenon in a Piping System

배관계통에서의 열성층 현상 모사를 위한 수치해석

  • 정재욱 (성균관대학교 기계공학부) ;
  • 김선혜 (성균관대학교 기계공학부) ;
  • 장윤석 (성균관대학교 기계공학부) ;
  • 최재붕 (성균관대학교 기계공학부) ;
  • 김영진 (성균관대학교 기계공학부) ;
  • 김진수 (한국원자력안전기술원 기계재료실) ;
  • 정해동 (한국원자력안전기술원 기계재료실)
  • Published : 2009.05.01
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Abstract

In some portions of nuclear piping systems, stratification phenomena may occur due to the density difference between hot and cold stream. When the temperature difference is large, the stratified flow under diverse operating conditions can produce high thermal stress, which leads to unanticipated piping integrity issues. The objectives of this research are to examine controvertible numerical factors such as model size, grid resolution, turbulent parameters, governing equation, inflow direction and pipe wall. Parametric three-dimensional computational fluid dynamics analyses were carried out to quantify effects of these parameters on the accuracy of temperature profiles in a typical nuclear piping with complex geometries. Then, as a key finding, it was recommended to use optimized mesh of real piping with the conjugated heat transfer condition for accurate thermal stratification analyses.

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References

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