Vortex and the Balance between Vorticity and Strain Rate

0503124 - ÚH 2020 RIV US eng J - Journal Article
Kolář, Václav - Šístek, Jakub
Vortex and the Balance between Vorticity and Strain Rate.
International Journal of Aerospace Engineering. Roč. 2019, March (2019), č. článku 1321480. ISSN 1687-5966. E-ISSN 1687-5974
R&D Projects: GA ČR(CZ) GA18-09628S
Institutional support: RVO:67985874 ; RVO:67985840
Keywords : vortex * vortex-idenfication methods * vortical structures * vorticity * strain rate
OECD category: Fluids and plasma physics (including surface physics); Applied mathematics (MU-W)
Impact factor: 1.230, year: 2019
Method of publishing: Open access

A new analysis of the vortex-identification Q-criterion and its recent modifications is presented. In this unified framework based on different approaches to averaging of the cross-sectional balance between vorticity and strain rate in 3D, new relations among the existing modifications are derived. In addition, a new method based on spherical averaging is proposed. It is applicable to compressible flows, and it inherits a duality property which allows its use for identifying high strain-rate zones together with vortices. The new quantity is applied to identification of vortices and high strain-rate zones in the flow around an inclined flat plate, in the flow past a sphere, and for the reconnection process of two Burgers vortices.
Permanent Link: http://hdl.handle.net/11104/0294945