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http://dx.doi.org/10.6110/KJACR.2011.23.5.365

Measurements of Velocity Distribution Function in Circular Open Channel Flows by Stereoscopic PIV  

Yoon, Ji-In (Graduate School of NID Fusion Technology, Seoul National University of Science and Technology)
Sung, Jae-Yong (Department of Mechanical Engineering, Seoul National University of Science and Technology)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.23, no.5, 2011 , pp. 365-374 More about this Journal
Abstract
For the first time, the present study has measured the velocity distribution function in circular open channel flow in a three-dimensional shape using a stereoscopic PIV system. For a given channel slope, water depth was varied from 30% to 80% of the channel diameter. Then, the characteristics of the velocity distribution function was compared according to the change of the water depth. Unlike a rectangular channel, the present experiment exhibited quite different shapes in the velocity distribution function whether the water depth is higher than 50% or not. Especially, the position of maximum velocity in the central and side wall changes in a different manner for the water depth above 50%. By differentiating the velocity distribution function, local wall friction coefficient was evaluated as a function of wall position. If the water depth goes down, the difference between the maximum and minimum values in the local wall friction coefficient increases, and the averaged value a1so increases.
Keywords
Circular open channel; Stereoscopic PIV; Velocity distribution function; Friction coefficient; Manning equation;
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Times Cited By KSCI : 1  (Citation Analysis)
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