Streamwise and spanwise vortical structure merging inside the wake of an inclined flat plate

0517335 - ÚT 2020 RIV FR eng J - Článek v odborném periodiku
Procházka, Pavel P. - Uruba, Václav
Streamwise and spanwise vortical structure merging inside the wake of an inclined flat plate.
Mechanics & Industry. Roč. 20, č. 7 (2019), č. článku 705. ISSN 2257-7777. E-ISSN 2257-7750
Grant CEP: GA ČR GA17-01088S
Institucionální podpora: RVO:61388998
Klíčová slova: flow instability * vorticity * wake * PIV * POD
Obor OECD: Applied mechanics
Impakt faktor: 0.874, rok: 2019
Způsob publikování: Open access
https://www.mechanics-industry.org/articles/meca/full_html/2019/07/mi190113/mi190113.html

The aim of this paper is to study the physics related to lift generation on an airfoil. A new hypothesis [1] of physical mechanism of flight relies on existence of streamwise vortical structures above the wing and inside the wake. The vortices origin as a consequence of flow instability inside the boundary layer developed under adverse pressure gradient. These structures are highly dynamical in nature, they change position and size very rapidly. A simple airfoil in the form of a flat plate with moderate angle of attack is considered in the presented research generate suitable flow at rather low Reynolds number. Stereo PIV time resolved measurement technique is used to capture high-dynamic data in several planes which are located in the wake and are perpendicular to freestream or parallel to the airfoil. The overall image of the flow field dynamics will be created using POD decomposition. Distinct flow patterns with associated kinetic energy are to be described as well as their role in the studied case. Existence of streamwise vorticity is proved, topology and other parameters are estimated in the paper, however related pressures and forces are not evaluated.
Trvalý link: http://hdl.handle.net/11104/0302958