Hostname: page-component-745bb68f8f-cphqk Total loading time: 0 Render date: 2025-01-09T05:54:48.705Z Has data issue: false hasContentIssue false
  • English
  • Français

Numerical processing of flow-visualization pictures – measurement of two-dimensional vortex flow

Published online by Cambridge University Press:  20 April 2006

Kensaku Imaichi  and
Kazuo Ohmi
Kensaku Imaichi
Affiliation:
Faculty of Engineering Science, Osaka University, Toyonaka. Japan
Kazuo Ohmi
Affiliation:
Faculty of Engineering Science, Osaka University, Toyonaka. Japan
Get access Rights & Permissions [Opens in a new window]

Abstract

A new system has been developed for estimating experimentally some of the principal physical variables of fluid flows, through flow-visualization and image-processing techniques. Distributions of stream function, vorticity and pressure are calculated by this system with reasonable accuracy for two examples of two-dimensional flow: namely unsteady twin-vortex flow behind a circular cylinder accelerated impulsively to constant speed, and Kármán vortices behind a circular cylinder moving at constant speed. A detailed explanation of the image-processing technique and the numerical calculation process is given first, and then some consideration is given to calculated results in these two types of flow. Comparison shows that some results of the unsteady twin-vortex experiment coincide well with those of previously published experimental investigations and theoretical calculations. Errors introduced at each stage of this system are estimated in some detail.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 129 , April 1983 , pp. 283 - 311
Copyright
© 1983 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Apelt, C. J. 1958 The steady flow of a viscous fluid past a circular cylinder at Reynolds numbers 40 and 44. Aero. Res. Counc. R. & M. no. 3175.Google Scholar
Bouard, R. & Coutanceau, M. 1980 The early stage of development of the wake behind an impulsively started cylinder for 40 Re 104. J. Fluid Mech. 101, 583.Google Scholar
Collins, W. M. & Dennis, S. C. R. 1973 Flow past an impulsively started circular cylinder J. Fluid Mech. 60, 105.Google Scholar
Coutanceau, M. & Bouard, R. 1977a Experimental determination of the main features of the viscous flow in the wake of a circular cylinder in uniform translations. Part 1. Steady flow. J. Fluid Mech. 79, 231.Google Scholar
Coutanceau, M. & Bouard, R. 1977b Experimental determination of the main features of the viscous flow in the wake of a circular cylinder in uniform translations. Part 2. Unsteady flow. J. Fluid Mech. 79, 256.Google Scholar
Hamielec, A. E. & Raal, J. D. 1969 Numerical studies of viscous flow around circular cylinders Phys. Fluids 12, 11.Google Scholar
Honji, H. & Taneda, S. 1969 Unsteady flow past a circular cylinder J. Phys. Soc. Japan 27, 1668.Google Scholar
Patel, V. A. 1976 Time-dependent solutions of the viscous incompressible flow past a circular cylinder by the method of series truncation Comp. Fluids 4, 13.Google Scholar
Schwabe, M. 1935 Über die Druckermittlung in der nichtstationären ebenen Strömung Ing. Arch. 6, 34.Google Scholar
Son, J. S. & Hanratty, T. J. 1969 Numerical solutions for the flow around a cylinder at Reynolds numbers of 40, 100 and 500 J. Fluid Mech. 35, 369.Google Scholar
Timme, A. 1957 Über die Geschwindigkeitsverteilung in Wirbeln Ing. Arch. 25, 205.Google Scholar