Temporal, Spatial, and Spatio-temporal correlation of the velocity fluctuations

0565485 - ÚT 2023 CZ eng C - Konferenční příspěvek (zahraniční konf.)
Jurčáková, Klára
Temporal, Spatial, and Spatio-temporal correlation of the velocity fluctuations.
International Workshop on Physical Modeling of Flow and Dispersion Phenomena - Book of Abstracts. Prague: Institute of Thermomechanics of the Czech Academy of Sciences, 2022 - (Jurčáková, K.; Kellnerová, R.), s. 94-100. ISBN 978-80-87012-81-9.
[International Workshop on Physical Modeling of Flow and Dispersion Phenomena. Prague (CZ), 29.08.2022-31.08.2022]
Grant CEP: GA ČR(CZ) GA18-09539S; GA ČR(CZ) GA15-18964S; GA TA ČR(CZ) LTC20056
Institucionální podpora: RVO:61388998
Klíčová slova: frozen turbulence * wind tunnel * integral length scales * Particle Image Velocimetry
Obor OECD: Meteorology and atmospheric sciences

Taylor's hypothesis about frozen turbulence [1] says that if the turbulence intensity is small compared to the mean velocity then the advection of a turbulent flow field past a fixed point can be taken entirely due to the mean flow. This means that in the “frozen turbulent field” spatial and temporal dimensions can be interchanged. Although the main assumption of Taylor's hypothesis is not met in the atmospheric boundary layer (the intensity of turbulence is usually between 10 and 20%) the hypothesis is commonly used to calculate integral length scales of turbulent fields from point measurements. Particle image velocimetry with high temporal resolution (TR-PIV) allows us to analyze both temporal and spatial cross-correlations in the turbulent flow fields and to evaluate obtained results.
Trvalý link: https://hdl.handle.net/11104/0337622