A note on integral vortex strength

0340294 - ÚH 2010 RIV SK eng J - Journal Article
Kolář, Václav
A note on integral vortex strength.
Journal of Hydrology and Hydromechanics. Roč. 58, č. 1 (2010), s. 23-28. ISSN 0042-790X. E-ISSN 1338-4333
R&D Projects: GA AV ČR IAA200600801
Institutional research plan: CEZ:AV0Z20600510
Keywords : circulation * unsteady Taylor vortex * vortex intensity * vortex strength * vorticity * vorticity decomposition
Subject RIV: BK - Fluid Dynamics
Impact factor: 0.553, year: 2010

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 vortexstrength 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.
Permanent Link: http://hdl.handle.net/11104/0005764