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Numerical Analysis of Unsteady Heat Transfer for the Location Selection of Anti-freeze for the Fire Protection Piping with Electrical Heat Trace

소방 배관 동파방지용 열선의 위치 선정을 위한 비정상 열전달 수치해석

  • Choi, Myoung-Young (Fire Insurers Laboratories of Korea) ;
  • Lee, Dong-Wook (Dept. of Mechanical & Automotive Engineering, Seoul National Univ. of Science & Technology) ;
  • Choi, Hyoung-Gwon (Dept. of Mechanical & Automotive Engineering, Seoul National Univ. of Science & Technology)
  • 최명영 (한국화재보험협회 방재시험연구원) ;
  • 이동욱 (서울과학기술대학교 기계자동차공학과) ;
  • 최형권 (서울과학기술대학교 기계자동차공학과)
  • Received : 2014.01.08
  • Accepted : 2014.02.24
  • Published : 2014.02.28

Abstract

In this paper, the unsteady incompressible Navier-Stokes equations coupled with energy equation were solved to find out the optimal location of electrical heat trace for anti-freeze of water inside the pipe for fire protection. Since the conduction equation of pipe was coupled with the natural convection of water, the analysis of conjugate heat transfer was conducted. A commercial code (ANSYS-FLUENT) based on SIMPLE-type algorithm was used for investigating the unsteady flows and temperature distributions in water region. From the numerical experiments, the isotherms and the vector fields in water region were obtained. Furthermore, it was found that the lowest part of the pipe cross-section was an optimal position of electrical heat trace assuming the constant thermal expansion coefficient of water since the minimum temperature of the water with the position is higher than those with the other positions.

Keywords

Heat tracing;anti-freeze;CFD;Natural convection;Conjugate heat transfer

Acknowledgement

Supported by : 서울과학기술대학교

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