scholarly journals Flow and turbulence structure around a spur dike in a channel with a large scour hole

2011 ◽  
Vol 47 (12) ◽  
Author(s):  
Mete Koken ◽  
George Constantinescu
Keyword(s):  
Turbulence Structure ◽  
Spur Dike ◽  
Scour Hole

scholarly journals Velocity Field and Turbulence Structure around Spur Dikes with Different Angles of Orientation under Ice Covered Flow Conditions

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1844
Author(s):  
Rahim Jafari ◽  
Jueyi Sui
Keyword(s):  
Flow Characteristics ◽  
Ice Cover ◽  
Roughness Coefficient ◽  
Turbulence Structure ◽  
Flow Conditions ◽  
Spur Dike ◽  
Turbulence Structures ◽  
Scour Hole ◽  
Spur Dikes ◽  
Set Up

Spur dikes are well-known structures that are widely used in rivers and coastal regions. Depending on their types, sizes, and orientation angles, spur dikes can substantially change flow characteristics. Results of previous studies indicate that the presence of an ice cover in rivers can cause complicated flow structures. The present experimental study investigates velocity fields and turbulence structures in the vicinity of spur dikes under ice cover with different roughness coefficients. The spur dikes were set up at the following three angles of orientation, 90°, 60°, and 45°. Our results show that the strongest velocity fluctuation occurs immediately above the scour hole surface and very close to the dike tip. The increase in the dike angle toward upstream, the velocity component values increase, leads to a larger scour hole. Results show that an increase in dike angle of each 10° (from 45° to 90°) increases the scour depth between 5% and 10%, depending on flow conditions. Furthermore, the increase in the cover roughness coefficient and the blockage ratio of a spur dike leads to a further increase in turbulence kinetic energy and 3D velocity components values. The findings of this study imply that the appearance of an ice cover can increase turbulence intensities up to nearly 30%.

Formula Type of Local Scour Depth on Spur Dike Nose

2014 ◽  
Vol 641-642 ◽  
pp. 271-274
Author(s):  
Qiang Ying
Keyword(s):  
Formation Process ◽  
Local Scour ◽  
Scour Depth ◽  
Calculation Methods ◽  
Spur Dike ◽  
Scour Hole ◽  
Main Factors ◽  
Formula Type ◽  
Suggested Formula

This passage introduces the formation process of scour hole, analyzes the main factors contributed to the local scour hole’s depth and classifies today’s calculation methods of scour depth into three categories. Then, given the conditions where those methods can be applied and drawbacks of those methods, this article also recommends some suggested formula in calculation.

Experimental Study on the Effect of Froude Number on Temporal Variation of Scour around a T Shaped Spur Dike in a 90 Degree Bend

2011 ◽  
Vol 147 ◽  
pp. 75-79 ◽  
Author(s):  
Mohammad Vaghefi ◽  
Masoud Ghodsian ◽  
Arash Adib
Keyword(s):  
Experimental Study ◽  
Temporal Variation ◽  
Froude Number ◽  
Average Diameter ◽  
Clear Water ◽  
Spur Dike ◽  
Outer Banks ◽  
The Past ◽  
Scour Hole ◽  
Spur Dikes

In the past few decades, the use of spur dikes for stability of the outer banks of rivers has attracted the attention of hydraulic engineers. Setting spur dikes in the flow’s direction leads to local scour around the spur dike and changes the topography of the bed. This paper deals with the study of the temporal variation of the scour hole and topography of the bed around a T shaped spur dike located in a 90 degree bend. The experiments were carried out in a channel with a 90 degrees bend. Uniform sediments having an average diameter of 1.28mm were used under clear water condition. The effects of Froude number on the amount and the geometry of scour hole around a T shaped spur dike and the time variation of scour were investigated.

scholarly journals The 3-D Morphology Evolution of Spur Dike Scour under Clear-Water Scour Conditions

Water ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1583 ◽  
Author(s):  
Li Zhang ◽  
Hao Wang ◽  
Xianqi Zhang ◽  
Bo Wang ◽  
Jian Chen
Keyword(s):  
Shear Stress ◽  
Morphological Evolution ◽  
Golden Section ◽  
Evolution Process ◽  
Bed Shear Stress ◽  
Clear Water ◽  
Power Functions ◽  
Spur Dike ◽  
Evolution Characteristics ◽  
Scour Hole

By changing the alignment angle of spur dike, this study focused on the evolution of scour hole morphology in three alignments under clear-water scour conditions, including the 3-D structure of the scour hole, 2-D profile morphological evolution process and the evolution characteristics of the local bed shear stress. The results show that the plane area and volume of the scour hole both are power functions over time, which is similar to the evolution characteristics of scour depth. Local scour includes three stages: The initial stage, development stage and balance stage. The local bed shear stress presents successively: τb > τc, τb = τc and τb < τc. Based on this characteristic, the evolution mechanism between scour hole morphology and the local bed shear stress is further clarified. Furthermore, although the alignment of the spur dike significantly affects the longitudinal and vertical dimension erosion rates of the scour hole, the scour hole morphology is not only relatively constant but also has a specific proportion, and the evolution process is orderly in the whole process of evolution. To the scouring equilibrium state, the length of the scour hole on the upstream and downstream of the spur dike is approximately in line with the golden section feature. The related results provide technical support for scour parameter design and scour hole protection of spur dike in flood period.

Statistical Analysis of the Turbulence Structure Downstream of a Short Roughness Strip

2007 ◽  
Vol 34 (2) ◽  
pp. 179-190
Author(s):  
M. O. Oyewola ◽  
M. S. Adaramola ◽  
A. O. Olaberinjo ◽  
O. A. Obiyemi
Keyword(s):  
Statistical Analysis ◽  
Turbulence Structure ◽  
Roughness Strip

Turbulence structure in the spiral wake shed by a lifting wing

AIAA Journal ◽  
1998 ◽  
Vol 36 ◽  
pp. 658-660
Author(s):  
Joseph A. Miranda ◽  
William J. Devenport
Keyword(s):  
Turbulence Structure
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