Experimental study of the propagation of compression and expansion pulses in a sound beam in a highly nonlinear medium

The variation of the duration and amplitudes of compression and expansion pulses of a sound beam and the width of the beam are experimentally investigated in the near field of a plane piston radiation in a gas-liquid suspension. The results confirm that the nonlinearity of the medium accelerates the spreading of a sound beam of compression pulses and slows it down for expansion pulses. The duration of the compression pulses decreases in the course of propagation, and the rate of decrease is greater for a larger pulse amplitude. The duration of the expansion pulses remains constant.