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

• Journal title : Fire Science and Engineering
• Volume 29, Issue 6,  2015, pp.33-39
• Publisher : Korea Institute of Fire Science and Engineering
• DOI : 10.7731/KIFSE.2015.29.6.033
Title & Authors
Numerical Analysis of Unsteady Heat Transfer for Location Selection of CPVC Piping
Choi, Myoung-Young; Choi, Hyoung-Gwon;

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;
Language
Korean
Cited by
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