Abo Bibliothek: Guest
Eighth International Symposium on Turbulence and Shear Flow Phenomena
August, 28-30, 2013, Poitiers, Futuroscope, France

DOI: 10.1615/TSFP8

CHARACTERISTICS OF REYNOLDS STRESSES IN A TURBULENT BOUNDARY LAYER

pages 1-6
DOI: 10.1615/TSFP8.650
Get accessGet access

ABSTRAKT

Reynolds shear-stress events play an important role in turbulent boundary layers. To investigate their origin, we look at time resolved particle image velocimetry data in a streamwise wall-normal plane and investigate the interaction between large and small scale velocity fluctuations and their contribution to normal and shear stresses. Streamwise velocity fluctuations are found to be predominately large scale and wall-normal velocity fluctuations smaller scale. Their interaction results in shear-stress, which is mostly present in intermediate scales. By spatial decomposition of temporal spectra, we find that large spatial scales interact at large time-scales and small spatial scales at small time-scales. From conditioned temporal spectra, we find that large streamwise velocity fluctuations modulate the amplitude of small scales, which contribute to the normal and shear stresses. Conditioned wavenumber-frequency spectra of these small scales shows that the time evolution of small spatial scales is proportional to large scale streamwise velocity fluctuations.

Digitales Portal Digitale Bibliothek eBooks Zeitschriften Referenzen und Berichte Forschungssammlungen Preise und Aborichtlinien Begell House Kontakt Language English 中文 Русский Português German French Spain