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Title: Coupling of an acoustic wave to shear motion due to viscous heating

Abstract

Viscous heating due to shear motion in a plasma can result in the excitation of a longitudinal acoustic wave, if the shear motion is modulated in time. The coupling mechanism is a thermal effect: time-dependent shear motion causes viscous heating, which leads to a rarefaction that can couple into a longitudinal wave, such as an acoustic wave. This coupling mechanism is demonstrated in an electrostatic three-dimensional (3D) simulation of a dusty plasma, in which a localized shear flow is initiated as a pulse, resulting in a delayed outward propagation of a longitudinal acoustic wave. This coupling effect can be profound in plasmas that exhibit localized viscous heating, such as the dusty plasma we simulated using parameters typical of the PK-4 experiment. We expect that a similar phenomenon can occur with other kinds of plasma waves.

Authors:
;  [1]
  1. Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242 (United States)
Publication Date:
OSTI Identifier:
22600007
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DUSTS; EXCITATION; HEATING; PLASMA SIMULATION; PLASMA WAVES; PULSES; SHEAR; SOUND WAVES; THREE-DIMENSIONAL CALCULATIONS; TIME DEPENDENCE; VISCOSITY

Citation Formats

Liu, Bin, and Goree, J. Coupling of an acoustic wave to shear motion due to viscous heating. United States: N. p., 2016. Web. doi:10.1063/1.4956444.
Liu, Bin, & Goree, J. Coupling of an acoustic wave to shear motion due to viscous heating. United States. doi:10.1063/1.4956444.
Liu, Bin, and Goree, J. 2016. "Coupling of an acoustic wave to shear motion due to viscous heating". United States. doi:10.1063/1.4956444.
@article{osti_22600007,
title = {Coupling of an acoustic wave to shear motion due to viscous heating},
author = {Liu, Bin and Goree, J.},
abstractNote = {Viscous heating due to shear motion in a plasma can result in the excitation of a longitudinal acoustic wave, if the shear motion is modulated in time. The coupling mechanism is a thermal effect: time-dependent shear motion causes viscous heating, which leads to a rarefaction that can couple into a longitudinal wave, such as an acoustic wave. This coupling mechanism is demonstrated in an electrostatic three-dimensional (3D) simulation of a dusty plasma, in which a localized shear flow is initiated as a pulse, resulting in a delayed outward propagation of a longitudinal acoustic wave. This coupling effect can be profound in plasmas that exhibit localized viscous heating, such as the dusty plasma we simulated using parameters typical of the PK-4 experiment. We expect that a similar phenomenon can occur with other kinds of plasma waves.},
doi = {10.1063/1.4956444},
journal = {Physics of Plasmas},
number = 7,
volume = 23,
place = {United States},
year = 2016,
month = 7
}
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