In-plane thermal diffusivity measurement of thin plates by the transient fin method

Abstract

The transient fin method has mainly be used for the measurement of in-plane thermal diffusivity of rather highly diffusive materials available under the form thin plates. This paper presents an extension of the method to low diffusivity materials such as plastics. An new analytical model is used in the real space, avoiding to make a Laplace transform of experimental temperatures recordings that may be inaccurate. Experiments carried on two materials under gas pressure varying from 10-2 mbar to 1 bar shows the great influence of heat conduction in the air surrounding the sample, leading to estimation errors that can reach 30% at atmospheric pressure. The experimental results also shows that accurate measurements can be achieved if the pressure is lower than 10-2 mbar.