A note on integral vortex strength

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A note on integral vortex strength

Controversial aspects of the conventional and widely used concept of the integral vortex strength are briefly discussed. The strength of a vortex is usually calculated as the circulation along the vortex boundary, or equivalently due to Green's theorem, as the surface integral of vorticity over the planar vortex cross section. However, the local effect of an arbitrary "superimposed shear" is fully absorbed by vorticity what makes the circulation a shear-biased vortex characteristic. The present paper shows that different vortex-strength models can be derived on the basis of different local vortex intensities proposed in the literature. The outcome of these models naturally differs, even for an ideally axisymmetric vortex. Three different vortex-strength models are compared and discussed by examining the unsteady Taylor vortex.

BATCHELOR G. K., 1967: An Introduction to Fluid Dynamics. Cambridge University Press.

GREEN S. I., 1995: Fluid Vortices. Kluwer.

KOLÁŘ V., 2007: Vortex identification: New requirements and limitations. Int. J. Heat Fluid Flow, 28, 638-652.

KOLÁŘ V., 2008: On the relationship between a vortex and vorticity. Abstracts of the IUTAM Symposium "150 Years of Vortex Dynamics", Lyngby-Copenhagen (Denmark) http://www.fluid.dtu.dk/English/Symposia/IUTAM_symposium/Program.aspx

KOLÁŘ V., SAVORY E., 2007: Dominant flow features of twin jets and plumes in crossflow. J. Wind Eng. Ind. Aerodyn., 95, 1199-1215.

PANTON R. L., 1984: Incompressible Flow. Wiley.

SAFFMAN P. G., 1992: Vortex Dynamics. Cambridge University Press.

ZHOU J., ADRIAN R. J., BALACHANDAR S., KENDALL T. M., 1999: Mechanisms for generating coherent packets of hairpin vortices in channel flow. J. Fluid Mech., 387, 353-396.

Journal of Hydrology and Hydromechanics

The Journal of Institute of Hydrology SAS Bratislava and Institute of Hydrodynamics CAS Prague

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