Turbulent Effects on the Settling Velocity of Suspended Sediment
Publication: Journal of Hydraulic Engineering
Volume 134, Issue 2
Abstract
The mean settling velocities of suspended sediments in turbulence have been examined. The settling velocities in a flume are directly measured by using an acoustic Doppler velocimeter. The results indicate the same trend as previous work in homogeneous isotropic turbulence. In addition to the flume experiment, the numerical experiments were conducted in the velocity field of homogeneous isotropic turbulence simulated by Kraichnan’s technique. The experimental and numerical results show that at high turbulence intensity the relative settling velocity increases with the increasing relative turbulence intensity regardless of the Stokes number. At intermediate turbulence intensity, it seems that the settling data bifurcate, i.e., the particles at the large Stokes number tend to be slowed, whereas the settling velocity of particles is increased at the small Stokes number.
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Acknowledgments
The writers owe thanks to Professor Peter Nielsen (The University of Queensland) for his valuable advice and assistance. They also would like to thank an anonymous editor. His comments were appreciated in the revision of the paper. Lastly, they wish to thank the River Fund, Electric Technology Research Foundation of Chugoku, and the Grants-in-Aid for Scientific Research by JSPS for financial support.
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Information
Published In
Journal of Hydraulic Engineering
Volume 134 • Issue 2 • February 2008
Pages: 261 - 266
Copyright
© 2008 ASCE.
History
Received: May 5, 2006
Accepted: May 1, 2007
Published online: Feb 1, 2008
Published in print: Feb 2008
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