Research in high intensity sound

During the period 1 November 1970 to 31 October 1975 basic research in nonlinear acoustics was carried out. The research, which was both theoretical and experimental, may be separated into three major areas. In one area N waves from electric sparks were used to study propagation, focusing, and diffraction of high intensity transient waves. Research was conducted on periodic finite-amplitude waves in a second area. In particular the author studied propagation in tubes, horns, and open media; propagation in inhomogeneous media; acoustic saturation; directional characteristics of beams; and suppression of sound by sound. Finally research was done on the propagation of finite-amplitude noise, both in tubes and in open media.