Author(s): A. Zeris; P. Prinos
Linked Author(s): Panagiotis Prinos
Keywords: Open-channel flow; Suction; Turblence; Lda; Hot-film; Anemometry
Abstract: The effects of bed suction on the structure of uniform fully developed turbulent open channel flow are studied experimentally with Laser-Doppler and Hot Film Anemometry. The influence of bed suction on the mean and rms velocity before, within and after the suction region are investigated for suction rates (based on discharges ratio) ranging from 1% to8%. Changes in the velocity profile, the near-wall turbulent intensities and the Reynolds shear stresses are observed. Such changes are more pronounced with increasing suction rate. Variations of flow depth before, within and after the suction region are measured, the constant of the law of the wall for uniform fully developed open channel flow (with no suction) changes and turbulence levels and Reynolds stresses are reduced with suction in the near bed region with increasing suction rate. Skewness and flatness as well as spectral estimates indicate the effects of bed suction on the structure of turbulence.
Year: 2001