The Impact of Vegetation on ohe Characteristics of the Flow in an Inclined Open Channel Using the Piv Method
Journal of Water Resources and Ocean Science
Volume 1, Issue 1, December 2012, Pages: 1-8
Received: Dec. 15, 2012;
Published: Dec. 30, 2012
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Keramaris Evangelos, Department of Civil Engineering, Division of Hydraulic and Environmental Engineering, University of Thessaly, Pedion Areos, Volos, Greece
In this study, the impact of vegetation on the characteristics of the flow in an inclined open channel is studied experimentally using a Particle Image Velocimetry (PIV). This optical method of fluid visualization is used to obtain in-stantaneous velocity measurements related properties in the fluids. For the simulation of vegetated bed, flexible vegetation with grass with different height (2.5 cm and 5 cm) with the same porosity (ε=0.75) were used. These conditions can be commonly found in systems with sediment transport. Twenty-four (24) experiments were conducted, twelve (12) with the flexible vegetation of 2.5 cm and twelve (12) with the flexible vegetation of 5 cm. The slope of the channel was kept equal to S=2‰, S=4‰ and S=6‰. The experiments were conducted in the laboratory of Hydraulics in the department of Civil Infrastructure Engineering of Alexander Technological Educational Institute of Thessaloniki, Greece. The channel has a length of 6.5 m, width of 7.5 cm and height of 25 cm. The impact of the channel slope, the vegetation height, the vegetation length and the relative vegetation depth on the characteristics of the flow is studied. Measurements of velocity were taken for horizontal channel slope at different heights using the PIV. Results show that the bed type can significantly influence the characteristics of the flow.
The Impact of Vegetation on ohe Characteristics of the Flow in an Inclined Open Channel Using the Piv Method, Journal of Water Resources and Ocean Science.
Vol. 1, No. 1,
2012, pp. 1-8.
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