The use of radiation pressure effect to measure energy losses of an ultrasonic beam during it's passage through an inhomogeneous solid layer placed into the liquid

When an acoustic wave passes through a solid layer located in the liquid, energy losses arise, caused both by absorption in the layer and by reflections from its boundaries. Since a layer inhomogeneous in thickness causes appreciable distortions of the wave front, the traditional method of measuring losses, based on recording the decrease in the amplitude of a plane wave, turns out to be inapplicable. Under these conditions, it is required to measure the wave power by a method that is not sensitive to the amplitude-phase structure of the acoustic field. In this paper, we propose an approach based on measuring the radiation force exerted by an ultrasonic beam on an extended absorber.