Acoustic shock and acceleration waves in selected inhomogeneous fluids

R. S. Keiffer; P. M. Jordan; I. C. Christov

doi:10.1016/j.mechrescom.2017.11.003

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arXiv · 1711.09451

Acoustic shock and acceleration waves in selected inhomogeneous fluids

R. S. Keiffer·P. M. Jordan·I. C. Christov

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Abstract

Acoustic shock and acceleration waves in inhomogeneous fluids are investigated using both analytical and numerical methods. In the context of start-up signaling problems, and based on linear acoustics theory, we study the propagation of such waveforms in the atmosphere and in fluids that possess a periodic ambient density profile. It is shown that vertically-running shock and acceleration waves in the atmosphere suffer amplitude growth. In contrast, those in the periodic-density fluid have bounded amplitudes that exhibit periodic, but non-trivial, oscillations; this is illustrated via a series of numerically-generated profile-evolution plots, which were computed using the PyClaw software package.

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R. S. Keiffer, P. M. Jordan, I. C. Christov. 2017-11-26. Acoustic shock and acceleration waves in selected inhomogeneous fluids. https://doi.org/10.1016/j.mechrescom.2017.11.003

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