scholarly journals A Study on the Secondary Flow in Open Channel Bend with Transverse Sloping Bed

1984 ◽  
Vol 28 ◽  
pp. 751-755
Keyword(s):  
Secondary Flow ◽  
Open Channel ◽  
Channel Bend ◽  
Sloping Bed

scholarly journals Laboratory Study of Secondary Flow in an Open Channel Bend by Using PIV

Water ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 659 ◽  
Author(s):  
Ruonan Bai ◽  
Dejun Zhu ◽  
Huai Chen ◽  
Danxun Li
Keyword(s):  
Secondary Flow ◽  
Open Channel ◽  
Three Dimensional ◽  
Secondary Flows ◽  
High Precision Measurement ◽  
Long Distance ◽  
Channel Bend ◽  
Image Velocimetry ◽  
Particle Image Velocimetry Method ◽  
Flow Circulation

The present paper aims to gain deeper insight into the evolution of secondary flows in open channel bend. A U-shaped open channel with long straight inflow/outflow reaches was used for experiments. Efforts were made to precisely specify flow conditions and to achieve high precision measurement of quasi-three-dimensional velocities with a multi-pass, two-dimensional PIV (Particle Image Velocimetry) method. The experimental results show that the flow begins to redistribute before entering the bend and it takes a long distance to re-establish to uniform conditions after exiting the bend. Complex secondary flow patterns were found to be present in the bend, as well as in the straight inflow and outflow reaches. A “self-breaking” (process was identified, which correlates stream-wise velocity with the intensity of flow circulation.

scholarly journals Flat vs. curved rigid-lid LES computations of an open-channel confluence

2019 ◽  
Vol 21 (2) ◽  
pp. 318-334 ◽  
Author(s):  
Pedro Xavier Ramos ◽  
Laurent Schindfessel ◽  
João Pedro Pêgo ◽  
Tom De Mulder
Keyword(s):  
Free Surface ◽  
Secondary Flow ◽  
Open Channel ◽  
Pressure Field ◽  
Large Eddy Simulations ◽  
Numerical Treatment ◽  
Mean Flow ◽  
Large Eddy ◽  
Flow Case ◽  
Channel Confluence

Abstract This paper describes the application of four Large Eddy Simulations (LES) to an open-channel confluence flow, making use of a frictionless rigid-lid to treat the free-surface. Three simulations are conducted with a flat rigid-lid, at different elevations. A fourth simulation is carried out with a curved rigid-lid which is a closer approximation to the real free-surface of the flow. The curved rigid-lid is obtained from the time-averaged pressure field on the flat rigid-lid from one of the initial three simulations. The aim is to investigate the limitations of the free-surface treatment by means of a rigid-lid in the simulation of an asymmetric confluence, showing the differences that both approaches produce in terms of mean flow, secondary flow and turbulence. After validation with experimental data, the predictions are used to understand the differences between adopting a flat and a curved rigid-lid onto the confluence hydrodynamics. For the present flow case, although it was characterized by a moderately low downstream Froude number (Fr ≈ 0.37), it was found that an oversimplification of the numerical treatment of the free-surface leads to a decreased accuracy of the predictions of the secondary flow and turbulent kinetic energy.

Secondary flow in sharp open-channel bends

2004 ◽  
Vol 498 ◽  
pp. 353-380 ◽  
Author(s):  
K. BLANCKAERT ◽  
H. J. De VRIEND
Keyword(s):  
Secondary Flow ◽  
Open Channel
Sign in / Sign up

Export Citation Format

Share Document