Impact of Proximity to Spires on Turbulent Characteristics and Structures

0480521 - ÚT 2018 FR eng C - Conference Paper (international conference)
Kellnerová, Radka - Jurčáková, Klára - Procházka, Pavel P. - Skála, Vladislav - Jaňour, Zbyněk
Impact of Proximity to Spires on Turbulent Characteristics and Structures.
PHYSMOD 2017. Nantes: LHEEA-DAUC, Ecole Centrale de Nantes, 2017.
[PHYSMOD 2017. Ecole Centrale de Nantes (FR), 23.08.2017-25.08.2017]
R&D Projects: GA ČR GA15-18964S
Institutional support: RVO:61388998
Keywords : spires * wind tunnel * vorticity * quadrant analysis * wavelet analysis
Subject RIV: DG - Athmosphere Sciences, Meteorology
https://physmod2017.sciencesconf.org/data/pages/book_physmod2017_en.pdf

Vertically truncated triangular spires (Irwin type) are applied to enhance turbulent diffusion from a surface upwards in order to increase an atmospheric boundary layer depth in wind tunnels. This paper studies the influence of variable upstream distances of spires on velocity statistics and formation of both vortical and non-vortical organized structures inside a test section. The 2C 2D time-resolved particle image velocimetry measured 2D streamwise-wall normal plane in the wind tunnel with a rough surface. Intermittent flow dynamics was evaluated by means
of skewness, cross-moments, vorticity, quadrant and wavelet analysis. The downstream evolution of the flow suggests that equilibrium between roughness- and spires-produced turbulence was reached in terms of statistics at the distance of seven spires height.
Permanent Link: http://hdl.handle.net/11104/0279412