Ondes acoustiques dans un guide aleatoire

Harmonic longitudinal acoustical waves are propagated through elastic thin rods whose elastic constant, density and crosssectional area are random functions of distance along the bar from a point of excitation. Partial reflection on successive inhomogeneities reduce the mean amplitude of waves, according to an exponential law, from the point of excitation. A method for calculating the mean damping coefficient is given, and the result is checked against numerical simulations.