TRANSFER-MATRIX ESTIMATION OF A THERMOELASTIC ACOUSTIC DISTURBANCE INDUCED IN A LAYERED MEDIUM BY HEAT-SOURCES

The problem of thermal excitation of a thermoelastic disturbance in a plane layered medium is solved by the transfer matrix method with allo wance for the interaction of thermal and elastic waves reflected from layer boundaries. The heat source density is nonuniform in the directi on perpendicular to the layers and is a harmonic function of time. The general solution to this problem is used to calculate the amplitude o f the acoustic signal in the gas-microphone version of the method of p hotoacoustic spectroscopy. Results are compared with the existing mode ls, and their applicability limits are determined. The solution can be used for interpreting the results of photo(thermo)acoustic or phototh ermal studies of layered media.