scholarly journals Boulder Array Effects on Bedload Pulses and Depositional Patches

2018 ◽  
Vol 123 (11) ◽  
pp. 2925-2953 ◽  
Author(s):  
A. N. (Thanos) Papanicolaou ◽  
Achilleas G. Tsakiris ◽  
Micah A. Wyssmann ◽  
Casey M. Kramer
Keyword(s):  
Boulder Array

Effects of a fully submerged boulder within a boulder array on the mean and turbulent flow fields: Implications to bedload transport

2012 ◽  
Vol 60 (6) ◽  
pp. 1502-1546 ◽  
Author(s):  
Athanasios N. Papanicolaou ◽  
Casey M. Kramer ◽  
Achilleas G. Tsakiris ◽  
Thorsten Stoesser ◽  
Sandeep Bomminayuni ◽  
...  
Keyword(s):  
Turbulent Flow ◽  
Flow Fields ◽  
Bedload Transport ◽  
The Mean ◽  
Boulder Array

Flow Structures in the Vicinity of a Submerged Boulder within a Boulder Array

2017 ◽  
Vol 143 (5) ◽  
pp. 04016104 ◽  
Author(s):  
Abul Basar M. Baki ◽  
Wenming Zhang ◽  
David Z. Zhu ◽  
Nallamuthu Rajaratnam
Keyword(s):  
Flow Structures ◽  
Boulder Array

scholarly journals Experimental investigation of turbulent flows through a boulder array placed on a permeable bed

2020 ◽  
Vol 20 (4) ◽  
pp. 1281-1293
Author(s):  
Hui Cao ◽  
Chen Ye ◽  
Xu-Feng Yan ◽  
Xing-Nian Liu ◽  
Xie-Kang Wang
Keyword(s):  
Turbulent Flows ◽  
Turbulence Intensity ◽  
Diffusion Processes ◽  
Quadrant Analysis ◽  
Turbulence Structure ◽  
Reynolds Stresses ◽  
Mean Flow ◽  
Flume Experiments ◽  
Budget Analysis ◽  
Boulder Array

Abstract Glass beads were used to model permeable beds and boulders (simulated by plastic spherical balls) placed on the centre section of the bed. Flume experiments were conducted to investigate the hydrodynamics through a boulder array over impermeable and permeable beds (i.e. IMPB and PB). For background reference, hydrodynamics investigation was made over smooth beds (SB) with the boulder array. Through measuring the instantaneous velocity field, the major flow characteristics such as mean flow velocity, turbulence intensity, turbulent kinetic energy (TKE) and instantaneous Reynolds stresses (through quadrant analysis) were presented. The results show that the increase in bed permeability through decreasing the exposure height of boulders has little impact on the magnitude of streamwise velocity, but tends to decrease the near-bed velocity gradient, thus affecting the bed shear-stress. For turbulence, similar to the previous studies, the bed permeability is identified to enable a downward shift of the peak of turbulence intensity. The TKE budget analysis shows that bed permeability tends to inhibit the transport and diffusion processes of TKE generation. Finally, the quadrant analysis of turbulence structure clearly shows that the ejections (Q2) and sweeps (Q4) with and without the boulder array are dominated by turbulence structure of different scales.

Influence of collective boulder array on the surrounding time-averaged and turbulent flow fields

2014 ◽  
Vol 11 (6) ◽  
pp. 1420-1428 ◽  
Author(s):  
Achilleas G. Tsakiris ◽  
A. N. Thanos Papanicolaou ◽  
Seyed M. Hajimirzaie ◽  
James H. J. Buchholz
Keyword(s):  
Turbulent Flow ◽  
Flow Fields ◽  
Boulder Array
Sign in / Sign up

Export Citation Format

Share Document