Contents: 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001

2021, 1

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

Download article (PDF, 598 kb)

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.

REFERENCES

1. Voronkov S.S. On the mechanism of generation of vortex tubes in the boundary layer of a viscous gas. Electronic journal "Technical Acoustics", http://www.ejta.org, 2020, 2.
2. Davidson, P. A. Turbulence: an introduction for scientists and engineers. Oxford, UK: Oxford University Press, 2004. – 680 p.
3. Garbaruk A. V. Transition to turbulence. Lecture 2. – S-P.: SPbSPU, 2019. – 35 p. Access mode: https://cfd.spbstu.ru/agarbaruk/turb_models/Term8_Lec02_transition.pdf
4. Loytsyanskiy L.G. Mechanics of liquid and gas. Ed. 5th. – M.: Nauka, 1978. – 736 p.
5. Tadashi Utami, Tetsuo Ueno. Experimental study on the coherent structure of turbulent open-chanel flow using visualization and picture processing // J. Fluid Mech. 1987. V. 174. P. 399-440.
6. Khlopkov Yu. I., Zharov V.A., Gorelov S.L. Coherent structures in a turbulent boundary layer. – M.: MFTI, 2002. – 267 p.
7. Voronkov S.S. On the mechanism of emergence turbulent Emmons spots. Electronic journal "Technical Acoustics", http://www.ejta.org, 2020, 1.
8. Boyko A.V., Gorev V.N., Kozlov V.V. Transition to turbulence in boundary layers: Success and prospects. NSU Bulletin. Series: Physics. 2006. Volume 1, Issue 2. P. 21-28.
9. Kozlov G.V., Litvinenko Yu. A., Grek G.R., Sorokin A.M. On the mechanism of origin and development of coherent structures in laminar and turbulent round streams. NSU Bulletin. Series: Physics. 2008. Volume 3, Issue 1. P. 12-22.


 

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