Hot strip method: application to thermal characterisation of orthotropic media

International audienceThis study deals with determination of the thermal conductivity tensor for orthotropic media and more specifically for multilayers with isotropic thermal characteristics in the planes parallel to the layers. The work described has been conducted using two ordinary experimental devices: a device based on the hot-wire method and a device based on the hot-strip method. Hot-wire measurements give the thermal conductivity in the planes parallel to layers. Introducing this value in a model adequate to describe orthotropic behaviour and using an appropriate identification method, hot-strip measurements then give the transverse thermal conductivity. The validity of this approach is demonstrated by the results obtained on a stratified medium with known thermal characteristics. Then, transverse thermal measurements were made on a non-woven wood fibre insulator