A study of hydrodynamic viscous fluid flow parameters change regularities in case of a conical diffuser

Authors

DOI:

https://doi.org/10.15587/1729-4061.2022.261954

Keywords:

conical diffuser, velocity profile, pressure distribution, breaking point, viscous fluid, fluid flow

Abstract

Studies of patterns of changes in hydrodynamic parameters of the viscous incompressible fluid in a conical diffuser were conducted. The specificity of the viscous liquid flow in a conical diffuser is that the kinetic energy of the flow, depending on the opening angle, is converted into pressure energy. Depending on Reynolds numbers and diffuser opening angles, the velocity vector field is stationary. With an increase in the Reynolds number, the symmetry of the flow relative to the axis of the diffuser is broken. A general solution to the approximate Navier-Stokes equations is given, based on the diffuser opening angle and the Reynolds number. A method for integrating the boundary value problem has been developed, and the patterns of velocity changes across the diffuser length at a parabolic distribution of velocities in the inlet section are obtained. By integrating partial differential equations that match all boundary conditions, the solution to the boundary value problem can be found. Graphs of changes in radial and axial velocities along the length and with a fixed value of the opening angle are shown; the flow pattern and the transition of a single-mode flow to multimode regimes are obtained. For a fixed opening angle and Reynolds number, the conditions for flow separation from a fixed wall are derived, where the flow velocity changes the sign. A mixing process is observed in the multi-mode region, which is accompanied by numerous pulsation phenomena and an unstable diffuser operation, where the resulting solutions are inappropriate. Based on the results of the studies obtained, it is possible to correctly design a conical diffuser, namely, under the condition of non-separated flow, to choose the opening angle and its length.

Author Biographies

Arestak Sarukhanyan, National University of Architecture and Construction of Armenia

Doctor of Technical Sciences, Professor, Head of Department

Department Water Systems, Hydraulic Engineering and Hydropower

Yeghiazar Vardanyan, National University of Architecture and Construction of Armenia

Doctor of Technical Sciences, Professor, Rector

Garnik Vermishyan, National University of Architecture and Construction of Armenia

Candidate of Physics and Mathematics Sciences, Associate Professor

Department of Mathematics

References

  1. Jeffery, G. B. (1915). The two-dimensional steady motion of a viscous fluid. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, 29 (172), 455–465. doi: https://doi.org/10.1080/14786440408635327
  2. Hamel, G. (1917). Spiralförmige Bewegungen zäher Flüssigkeiten.. Jahresbericht der Deutschen Mathematiker-Vereinigung, 25, 34–60. Available at: https://gdz.sub.uni-goettingen.de/id/PPN37721857X_0025?tify={%22pages%22:[41],%22panX%22:0.487,%22panY%22:0.784,%22view%22:%22info%22,%22zoom%22:0.348}
  3. Targ, S. M. (1951). Osnovnye zadachi teorii laminarnykh techeniy. Moscow: Gostekhizdat, 420.
  4. Slezkin, N. A. (1955). Dinamika vyazkoy neszhimaemoy zhidkosti. Moscow: Gostekhizdat, 519.
  5. Tikhonov, A. N., Samarskiy, A. G. (1977). Uravneniya matematicheskoy fiziki. Moscow: Nauka, 735.
  6. Akulenko, L. D., Kumakshev, S. A. (2008). Bifurcation of multimode flows of a viscous fluid in a plane diverging channel. Journal of Applied Mathematics and Mechanics, 72 (3), 296–302. doi: https://doi.org/10.1016/j.jappmathmech.2008.07.007
  7. Kumakshev, S. A. (2020). Flat diffuser: Steady state flow of a viscous incompressible fluid. Engineering Journal: Science and Innovation, 7 (103). doi: https://doi.org/10.18698/2308-6033-2020-7-1993
  8. Volkov, E., Fedyushkin, A. (2019). Symmetry of the flow of Newtonian and non-Newtonian fluid in a flat diffuser and confusor. Physical-Chemical Kinetics in Gas Dynamics, 20 (2), 1–19. doi: https://doi.org/10.33257/phchgd.20.2.791
  9. Fedyushkin, A. I. (2016). The transition flows of a viscous incompressible fluid in a plane diffuser from symmetric to asymmetric and to non-stationary regimes. Physical-Chemical Kinetics in Gas Dynamics, 17 (3). Available at: http://chemphys.edu.ru/media/published/%D0%A1%D1%82%D0%B0%D1%82%D1%8C%D1%8F__%D0%A4%D0%B5%D0%B4%D1%8E%D1%88%D0%BA%D0%B8%D0%BD_%D0%90%D0%A4%D0%9C-10_2016_corr.pdf
  10. El-Behery, S. M., Hamed, M. H. (2011). A comparative study of turbulence models performance for separating flow in a planar asymmetric diffuser. Computers & Fluids, 44 (1), 248–257. doi: https://doi.org/10.1016/j.compfluid.2011.01.009
  11. Gerasimenko, V. P., Tkachuk, A. S., Ytsishin, A. A. (2012). About polars of straight-wall diffusers. Power and heat engineering processes and equipment, 8, 137–142. Available at: http://library.kpi.kharkov.ua/files/Vestniki/2012_8.pdf
  12. Haines, P. E., Hewitt, R. E., Hazel, A. L. (2011). The Jeffery–Hamel similarity solution and its relation to flow in a diverging channel. Journal of Fluid Mechanics, 687, 404–430. doi: https://doi.org/10.1017/jfm.2011.362
  13. Sarukhanyan, A., Vartanyan, A., Vermishyan, G., Tokmajyan, V. (2020). The Study of Hydrodynamic Processes Occurring on Transition of Sudden Expanding of Hydraulic Section of Plane – Parallel Full Pipe Flow. TEM Journal, 1494–1501. doi: https://doi.org/10.18421/tem94-23

Downloads

Published

2022-08-30

How to Cite

Sarukhanyan, A., Vardanyan, Y., & Vermishyan, G. (2022). A study of hydrodynamic viscous fluid flow parameters change regularities in case of a conical diffuser. Eastern-European Journal of Enterprise Technologies, 4(7 (118), 61–71. https://doi.org/10.15587/1729-4061.2022.261954

Issue

Vol. 4 No. 7 (118) (2022): Applied mechanics

Section

Applied mechanics

License

Copyright (c) 2022 Arestak Sarukhanyan, Yeghiazar Vardanyan, Garnik Vermishyan

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

The consolidation and conditions for the transfer of copyright (identification of authorship) is carried out in the License Agreement. In particular, the authors reserve the right to the authorship of their manuscript and transfer the first publication of this work to the journal under the terms of the Creative Commons CC BY license. At the same time, they have the right to conclude on their own additional agreements concerning the non-exclusive distribution of the work in the form in which it was published by this journal, but provided that the link to the first publication of the article in this journal is preserved.

A license agreement is a document in which the author warrants that he/she owns all copyright for the work (manuscript, article, etc.).
The authors, signing the License Agreement with TECHNOLOGY CENTER PC, have all rights to the further use of their work, provided that they link to our edition in which the work was published.
According to the terms of the License Agreement, the Publisher TECHNOLOGY CENTER PC does not take away your copyrights and receives permission from the authors to use and dissemination of the publication through the world's scientific resources (own electronic resources, scientometric databases, repositories, libraries, etc.).
In the absence of a signed License Agreement or in the absence of this agreement of identifiers allowing to identify the identity of the author, the editors have no right to work with the manuscript.
It is important to remember that there is another type of agreement between authors and publishers – when copyright is transferred from the authors to the publisher. In this case, the authors lose ownership of their work and may not use it in any way.