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Evaluation of Leak Rate Through a Crack with Linearly-Varying Sectional Area

선형적으로 변하는 단면적을 가진 균열에서의 누설률 평가

  • Park, Jai Hak (Dept. of Safety Engineering, Chungbuk Nat'l Univ.)
  • 박재학 (충북대학교 안전공학과)
  • Received : 2016.03.18
  • Accepted : 2016.08.03
  • Published : 2016.09.01

Abstract

The leak before break (LBB) concept is used in pipe line design for nuclear power plants. For application of the LBB concept, leak rates through cracks should be evaluated accurately. Usually leak late analyses are performed for through-thickness cracks with constant cross-sectional area. However, the cross-sectional area at the inner pipe surface of a crack can be different from that at the outer surface. In this paper, leak rate analyses are performed for the cracks with linearly-varying cross-sectional areas. The effect of varying the cross-sectional area on leak rates was examined. Leak rates were also evaluated for cracks in bi-material pipes. Finally, the effects of crack surface morphology parameters on leak rates were examined.

Keywords

Leak Rate;Through-thickness Crack;Modified Henry-Fauske Model;Pipe;Nuclear Power Plant

Acknowledgement

Supported by : 충북대학교

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