A new basic analysis of pulsed photoacoustic signal using the finite differences method

Pulsed photoacoustic spectroscopy provides information about optical, thermal and geometrical characteristics of opaque materials. The aim of this paper is the analysis of the applicability of the finite differences method to simulate the process by which pulsed photoacoustic signal is generated by a pulsed heat source, both in time and frequency domains. The present study is extended to a two-layers absorbing system. This method is free of the limitations imposed by special cases when the analytical methods are used to resolve heat diffusion equations. This approach is analyzed through the temperature and pressure variations in the photoacoustic cell.