Photothermal device for water dynamics measurement and thermophysical characterization: Application on textile samples

• Published in: Review of scientific instruments 2002-03, Vol.73 (3), p.1299-1303
• Main Authors: Duvaut, T., Limare, A., Bachmann, J. M.
• Format: Article
• Language: English
• ISSN: 0034-6748; 1089-7623
• DOI: 10.1063/1.1448902

The photopyroelectric method in a noncontact configuration (excitation source: diode laser at 1.94 μm) is capable of yielding information on the water content of a textile sample and on its influence on the thermal properties. A one-dimensional theoretical model was developed assuming the sample thermally homogeneous and taking into account the optical absorption and scattering. The experimental setup designed for this purpose included an excitation source resonant with water absorption, signal and data processing units and cells for conditioning the samples. We optimized the experimental conditions in order to identify the parameters related to the water content in the sample, and to monitor the dynamics of the process. The effective thermal conductivity and the volume specific heat were determined at different moments of time while the sample was taking up water. Two thermal parameters related to the comfort of a fabric were also calculated: the thermal effusivity and the thermal resistance.