Thermal diffusivity measurements in the photoacoustic open-cell configuration using simple signal normalization techniques

A generalized model for the open photoacoustic cell configuration (OPC) tec hnique, involving one-dimensional heat diffusion across two layers, is pres ented. The analytical results are particularly suitable for applications wi th dielectric solids, such as polymers and resins. Two effective normalizat ion procedures for simple and reliable measurement of the thermal diffusivi ty of this kind of materials using an OPC are also presented. The thermal d iffusivity of three different materials (a dental resin, an epoxy resin, an d a polymer foil) was measured and excellent agreement was obtained with so me values reported in the literature. (C) 2001 American Institute of Physic s.