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Development of numerical model for estimating thermal environment of underground power conduit considering characteristics of backfill materials

되메움재 특성을 고려한 전력구 열환경 변화 예측 수치해석모델 개발

  • Kim, Gyeonghun (Risk Management Research Center, Dongbu Insurance) ;
  • Park, Sangwoo (Department of Civil and Environmental Engineering, Sejong University) ;
  • Kim, Min-Ju (Korea Electric Power Research Institute) ;
  • Lee, Dae-Soo (Department chief, Korea Electric Power Research Institute) ;
  • Choi, Hangseok (School of Civil, Environmental and Architectural Engineering, Korea University)
  • Received : 2017.01.18
  • Accepted : 2017.03.10
  • Published : 2017.03.31

Abstract

The thermal analysis of an underground power conduit for electrical cables is essential to determine their current capacity with an increasing number of demands for high-voltage underground cables. The temperature rises around a buried cable, caused by excessive heat dissipation, may increase considerably the thermal resistance of the cables, leading to the danger of "thermal runaway" or damaging to insulators. It is a key design factor to develop the mechanism on thermal behavior of backfilling materials for underground power conduits. With a full-scale field test, a numerical model was developed to estimate the temperature change as well as the thermal resistance existing between an underground power conduit and backfill materials. In comparison with the field test, the numerical model for analyzing thermal behavior depending on density, moisture content and soil constituents is verified by the one-year-long field measurement.

Acknowledgement

Supported by : 한국전력연구원, 한국연구재단

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