Abstract
Anlaysis on energy reflection of plane waves impinging on an inhomogeneous multi-layer is presented. The variation of acoustic impedance through the individual inhomogeneous layer is defined by a linear function of the thickness coordinate z. Closed form analytical solutions of the coefficient of energy reflection and transmission are obtained for the normal incidence to show fundamental but reliable results. The discontinuity of acoustic impedance at interfaces affects dominantly on energy reflection. Then the explanation of the effect has been systematically with the variation of impedance.
It is possible to show that the model of linear inhomogeneous layer is equivalent to a stacked layer made of 12 homogeneous layers. The analytical model may be available effectively to a transitional layer of deteriorated bonding interface, and a layer of functionally gradient material and so forth.
