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You are here : eLibrary : IAHR World Congress Proceedings : 36th Congress - The Hague (2015) ALL CONTENT : Water engineering : The variation of turbulent eddy viscosity during a wave cycle
The variation of turbulent eddy viscosity during a wave cycle
Author : NELLY OLDEKOP(1) & TOOMAS LIIV(2)
ABSTRACT
One of the most problematic issues that have to be dealt with in connection with the surf zone hydrodynamics is the
accurate determination of turbulent eddy viscosity under breaking waves. Most hydrodynamic and sediment transport
models tend to neglect the unsteady character of this term. This means, that turbulent eddy viscosity on the seabed
changes both in time and space.
This paper focuses on the results obtained during experimental runs in the wave flume of Laboratory of Fluid Mechanics
in Tallinn University of Technology. Experiments were performed on the beach model with an inclination of 1 to 17.
Velocities were measured using 2D LDA apparatus in various profiles around the breaking point. Measurements were
performed extremely close to bed allowing the calculation of bottom shear stresses under wave.
The paper presents results of the study of turbulent eddy viscosity in the surf zone on the bottom of the hydraulically
smooth beach model. It was found that turbulent viscosity varies both in time and space as the wave propagates and is
at least an order of magnitude larger than the corresponding dynamic viscosity.
File Size : 626,881 bytes
File Type : Adobe Acrobat Document
Chapter : IAHR World Congress Proceedings
Category : 36th Congress - The Hague (2015) ALL CONTENT
Article : Water engineering
Date Published : 12/08/2015
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