Analysis of radiative heat transfer on measuring thermal conductivity of semi-transparent materials using transient plane source method

Hu Zhang*, Yueming Li, Wenquan Tao

*Corresponding author for this work

Research output: Chapter in Book or Report/Conference proceedingConference Proceedingpeer-review

Abstract

Aerogels have extremely low density, high porosity and superior insulation performance; therefore they have widespread application value and prospect. But they are semi-transparent for thermal radiation at high temperature. Thermal conductivity measurement is an important way of evaluating their thermal insulation performance. The theoretical basis of transient plane source method is based on unsteady differential equation of conduction which is suitable for opaque medium. For semi-transparent materials, radiation will participate in the thermal transport process. The existence of thermal radiation within the materials will affect the test accuracy. In present study, the effect of radiative heat transfer on determining thermal conductivity of semi-transparent materials using transient plane source method is numerically studied. Semi-transparent materials with different extinction coefficient are studied at different temperature by simulating 1 dimensional steady heat transfer process the same as the experiment of steady method. The calculated thermal conductivity is selected as reference for comparison with transient plane source method. The heat transfer process of applying transient plane source method to semi-transparent materials is mimicked numerically as experimental test of transient plane source method. The results show that the thermal conductivity of semi-transparent materials measured by transient plane source method will be overestimated at temperature higher than 600 K and extinction coefficient less than 2000 m-1where radiative heat transfer is dominant. The deviation increases with temperature and reaches to 19.6% at 1000 K and 500 m-1. It illustrates that radiative heat transfer will affect the thermal conductivity accuracy of semi-transparent materials.

Original languageEnglish
Title of host publicationProceedings of the 2nd Thermal and Fluid Engineering Summer Conference, TFESC 2017 and 4th International Workshop on Heat Transfer, IWHT 2017
PublisherBegell House Inc.
Pages421-432
Number of pages12
ISBN (Electronic)9781567004700
Publication statusPublished - 2017
Externally publishedYes
Event2nd Thermal and Fluid Engineering Summer Conference, TFESC 2017 and 4th International Workshop on Heat Transfer, IWHT 2017 - Las Vegas, United States
Duration: 2 Apr 20175 Apr 2017

Publication series

NameProceedings of the Thermal and Fluids Engineering Summer Conference
Volume2017-April
ISSN (Electronic)2379-1748

Conference

Conference2nd Thermal and Fluid Engineering Summer Conference, TFESC 2017 and 4th International Workshop on Heat Transfer, IWHT 2017
Country/TerritoryUnited States
CityLas Vegas
Period2/04/175/04/17

Keywords

  • Radiative heat transfer
  • Semi-transparent materials
  • Test accuracy
  • Thermal conductivity
  • Transient plane source method

Fingerprint

Dive into the research topics of 'Analysis of radiative heat transfer on measuring thermal conductivity of semi-transparent materials using transient plane source method'. Together they form a unique fingerprint.

Cite this