Sigve Tjo

TL;DR: In this article, the distortion and harmonic generation in the near field of a finite amplitude sound beam are considered, assuming time-periodic but otherwise arbitrary on-source conditions, and the amplitude and phase of the fundamental and first few harmonics are calculated along the beam axis, and across the beam at various ranges from the source.

TL;DR: In this paper, the propagation and interaction of two collinear finite amplitude sound beams were studied and the validity of the parabolic equation when applied to strongly focused sound beams was discussed.

TL;DR: Aanonsen et al. as discussed by the authors considered nonlinear propagation of a periodic sound beam in a dissipative fluid using Fourier series expansion and numerical methods to solve the governing equation of motion in the parabolic approximation.

TL;DR: In this article, the propagation and interaction of finite amplitude sound waves produced by a baffled piston source in a thermoviscous fluid are considered, and basic equations are derived and their ranges of validity established.

TL;DR: In this paper, a high intensity sound beam from a plane circular transducer is presented for a large range of excitation levels, and the ratio of the shock formation distance to the Rayleigh distance ranges from 1.7 to 0.06.