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Accession Number ADA570906
Title Propagation of Nonlinear Acoustic Waves in Viscous and Thermoviscous Fluids.
Publication Date 2012
Media Count 9p
Personal Author A. Warn-Varnas G. V. Norton P. M. Jordan S. A. Chin-Bing
Abstract Acoustic travelling waves are studied in the context of nonlinear propagation in Newtonian fluids. First we examine the one-dimensional (1D) versions of four weakly-nonlinear acoustic models, all of which admit known travelling wave solutions (TWS)s in the form of Taylor shocks. Next, we derive the exact but implicit, kink-type TWS of the compressible 1D Navier-Stokes equations under the homentropic assumption. Then, using three simple metrics, we numerically compare the TWSs of the former with that of the latter. It is shown that, while results for gases are mixed, in the case of liquids, the simple Burgers' equation yields the TWS that best approximates the profile of the Navier-Stokes equations. Lastly, an energy analysis of the weakly-nonlinear models is carried out, connections between the models are noted and new critical values of the physical parameters are presented.
Keywords Acoustic waves
Blsc(Blackstock lesser seebass crighton equations)
Burgers equations
Darbouxs equations
Energy analysis
Kuznetsovs equations
Lw(Lighthill-westervelt equations)
Mach number
Navier stokes equations
Newtonian fluids
Nonlinear acoustics
Reynolds number
Rsgc(Rasmussen sorensen gaididei christiansen equations)
Taylor shocks
Thermoviscous fluids
Traveling waves
Tws(Travelling wave solutions)
Viscous fluids
Wave speed

Source Agency Non Paid ADAS
NTIS Subject Category 46A - Acoustics
46B - Fluid Mechanics
Corporate Author Naval Research Lab. Detachment, Stennis Space Center, MS.
Document Type Journal article
Title Note Journal article.
NTIS Issue Number 1315
Contract Number N/A

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