Electronic Journal Technical Acoustics ISSN 1819-2408

S. Voronkov

On the emergence and decay of coherent vortex structures in a viscous gas

language: Russian

received 20.12.2020, published 23.01.2021

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ABSTRACT

The mechanism of emergence and decay of coherent vortex structures in the boundary layer on a plate and in a circular axisymmetric viscous gas jet is considered. It is noted that coherent vortex structures are present not only at the transition stage, but also in a developed turbulent flow of a viscous gas. It has been established that turbulence in a viscous heat-conducting gas is a cyclically repeating process of the emergence and decay of coherent vortex structures described by a vector wave equation. The decay of vortex structures is accompanied by an explosive, asymptotic increase in pressure pulsation, which triggers a new cycle of turbulence generation.

Keywords: coherent vortex structures, vector wave equation, boundary layer, circular jet, viscous gas.

8 pages, 4 figures

Сitation: S. Voronkov. On the emergence and decay of coherent vortex structures in a viscous gas. Electronic Journal “Technical Acoustics”, http://www.ejta.org, 2021, 1.

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Sergey S. Voronkov graduated from Leningrad Polytechnic Institute (Russia) in 1979, PhD. Presently he is docent at Pskov State University. Scientific area: hydrodynamics, nonlinear acoustics. e-mail: voronkovss(at)yandex.ru