A Scalar Acoustic Equation for Gases, Liquids, and Solids, Including Viscoelastic Media


The work deals with a mathematical model for real-time acoustic monitoring of material parameters of media in multi-state viscoelastic engineering systems continuously operating in irregular external environments (e.g., wind turbines in cold climate areas, aircrafts, etc.). This monitoring is a high-reliability time-critical task. The work consistently derives a scalar wave PDE of the Stokes type for the non-equilibrium part (NEP) of the average normal stress in a medium. The explicit expression for the NEP of the corresponding pressure and the solution-adequateness condition are also obtained. The derived Stokes-type wave equation includes the stress relaxation time and is applicable to gases, liquids, and solids.

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Mamontov, E. and Berbyuk, V. (2014) A Scalar Acoustic Equation for Gases, Liquids, and Solids, Including Viscoelastic Media. Journal of Applied Mathematics and Physics, 2, 960-970. doi: 10.4236/jamp.2014.210109.

Conflicts of Interest

The authors declare no conflicts of interest.


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