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Numerical Analysis of Unsteady Heat Transfer for Location Selection of CPVC Piping

CPVC 배관 동파방지용 열선의 위치 선정을 위한 비정상 열전달 수치해석

  • 최명영 (한국화재보험협회 방재시험연구원) ;
  • 최형권 (서울과학기술대학교 기계자동차공학과)
  • Received : 2015.09.14
  • Accepted : 2015.11.26
  • Published : 2015.12.31

Abstract

In this paper, a numerical experiment was conducted to find out the optimal location of electrical heat trace for anti-freeze of water inside the CPVC pipe for fire protection. The unsteady incompressible Navier-Stokes equations coupled with energy equation were solved. 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 present numerical experiment, it has been found that the vector field of water inside the PVC pipe is opposite to the case of steel because of the huge difference of material properties of the two pipes. Furthermore, it was found that the lowest part of the pipe was an optimal position for electrical heat trace since the minimum water temperature of the case was higher than those of the other cases.

Keywords

Heat tracing;CPVC;CFD;Natural convection;Conjugate heat transfer

Acknowledgement

Supported by : 서울과학기술대학교

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