Simple Evaluation Method for Effective Thermal Conductivity of a Wick Structure Filled with a Working Fluid

Yasushi Koito,Toshio Tomimura,Ryo Yamaguchi

doi:10.5098/fhp.7.3

Abstract

Simple Evaluation Method for Effective Thermal Conductivity of a Wick Structure Filled with a Working Fluid

Highlights

In mathematical modeling of a capillary-wick heat pipe, the effective thermal conductivity is often used to calculate the heat transfer through a wick structure (Faghri, 1995; Vadakkan et al, 2004; Koito et al, 2006)
The present study extends the above-mentioned simple measurement method to evaluate the effective thermal conductivity of a heat pipe wick structure filled with a working fluid
In the cases of spherical powders, the fairly good agreement was obtained between the measurement results and the Frontiers in Heat Pipes (FHP), 7, 3 (2016)

Summary

INTRODUCTION

In mathematical modeling of a capillary-wick heat pipe, the effective thermal conductivity is often used to calculate the heat transfer through a wick structure (Faghri, 1995; Vadakkan et al, 2004; Koito et al, 2006). The use of effective thermal conductivity simplifies the heat transfer calculation of a wick structure filled with a working fluid because they are modeled as a homogeneous medium. The thermal conductivity of a solid plate, on the other hand, can be measured by creating a steady-state one-dimensional temperature distribution in a sample (Tomimura et al, 2011). The value of thermal conductivity of a sample is obtained by using Fourier’s law This measurement method was applied for the study to evaluate the heat transfer between solid surfaces in contact (Koito et al, 2014). The present study extends the above-mentioned simple measurement method to evaluate the effective thermal conductivity of a heat pipe wick structure filled with a working fluid.

PRINCIPLE OF MEASUREMENT

38 Type 2

RESULTS AND DISCUSSION

CONCLUSIONS