That’s Shocking! The Physics of Nonlinear Sound Waves With Examples
Dr. Kent Gee
Department of Physics and Astronomy
Brigham Young University
Like other areas of physics, fascinating phenomena occur in
acoustics when amplitudes become large enough that the simplifying assumptions
we’re fond of making begin to break down.
The speed of sound is no longer the constant that we’re taught in
introductory physics – different parts of the wave travel at different speeds,
causing the wave’s shape to distort and shocks to form. What kind of amplitudes
are required for these shocks to form?
Where do they occur? What damage
can they cause? How can they be
mitigated or harnessed for our benefit? In this presentation, I’ll describe nonlinear
sound waves and shock formation and discuss examples from my research,
including military jet aircraft, rockets, Gatling guns, and explosions. I’ll also talk about sonic booms and their
mitigation, and how nonlinear sound waves can be used to break up kidney stones
and produce highly directional audio.