Radiative transfer problems in remote sensing of thermal diffusivity
| Parent link: | Materials Science Research Journal.— , 2007- Vol. 4, iss. 4.— 2010.— P. 415-446 |
|---|---|
| Main Author: | |
| Other Authors: | |
| Summary: | Thermal diffusivity is usually determined from measured temperature evolution when a sample is exposed to a transient energy source. In the majority of experiments reported in the literature, heat flow through the sample is considered as purely conductive. Instead, this paper investigates to which extent conduction coupled to radiation is reflected by the temperature evolution of thin films, and how this alters diffusivity if it is extracted from transient temperature using standard procedures. The analysis is applied to flash experiments using constant (independent of wavelength) extinction properties of thin films, and to periodic (intensity modulated) energy sources. Focussed on samples with optical thickness between 1 and 50, the results indicate that coupling between conduction and radiation may significantly alter thermal diffusivity if it is extracted from data taken at single surface positions only, or by any other technique that relies on coupling between surface temperature and temperature of a medium above the surface, like in mirage experiments. Uncertainties are expected also in intensity modulated experiments when diffusivity is determined from correlations with phase shifts. В фонде НТБ ТПУ отсутствует |
| Published: |
2010
|
| Subjects: | |
| Format: | Book Chapter |
| KOHA link: | https://koha.lib.tpu.ru/cgi-bin/koha/opac-detail.pl?biblionumber=599849 |