Direct numerical simulation of turbulent channel flow over a surrogate for Nikuradse-type roughness

M Thakkar, A Busse, ND Sandham - Journal of Fluid Mechanics, 2018 - cambridge.org
A tiled approach to rough surface simulation is used to explore the full range of roughness
Reynolds numbers, from the limiting case of hydrodynamic smoothness up to fully rough …

Boundary layer dynamics and bottom friction in combined wave–current flows over large roughness elements

X Yu, JH Rosman, JL Hench - Journal of Fluid Mechanics, 2022 - cambridge.org
In the coastal ocean, interactions of waves and currents with large roughness elements,
similar in size to wave orbital excursions, generate drag and dissipate energy. These …

Low relative-submergence effects in a rough-bed open-channel flow

M Rouzes, FY Moulin, E Florens… - Journal of Hydraulic …, 2019 - Taylor & Francis
Multi-plane stereoscopic PIV measurements were performed in an open-channel flume fitted
with cubes to investigate very low submergence ratios, h/k={1.5, 2, 3}, where h is the water …

Structure functions and invariants of the anisotropic Reynolds stress tensor in turbulent flows on water-worked gravel beds

N Penna, E Padhi, S Dey, R Gaudio - Physics of Fluids, 2020 - pubs.aip.org
In this paper, a statistical description of turbulence in flow on a water-worked gravel-bed is
presented by applying the laws of turbulence in conjunction with the double-averaging …

On the structure of turbulent gravel bed flow: Implications for sediment transport

SH Mohajeri, M Righetti, G Wharton… - Advances in Water …, 2016 - Elsevier
The main objective of this study was to examine the turbulent flow field over gravel particles
as a first step towards understanding sediment transport in a gravel bed river. Specifically …

Statistical characterization of unworked and water-worked gravel-bed roughness structures

N Penna, E Padhi, S Dey, R Gaudio - Journal of Hydraulic …, 2021 - Taylor & Francis
Gravel-bed roughness structures for an unworked bed and a water-worked bed are
analysed at different topographic scales measuring the bed surfaces by a 3D terrestrial laser …

Spatial structure of near-bed flow properties at the grain scale

J Groom, H Friedrich - Geomorphology, 2019 - Elsevier
Expanding the existing knowledge of the role of roughness on near-bed flow properties is
vital to provide deeper insights into the interactions between the flow, sediment transport …

Stereo-PIV measurements within the canopy in open-channel flows

M Trevisson, Y Akutina, O Eiff - Experiments in Fluids, 2024 - Springer
Measuring the flow field not just above but also inside the canopy of rough beds in open-
channel flows is challenging when optical access from below or the side is not possible. To …

Velocity Profiles in Gravel Beds Based on Refractive Index Matching Experiments

G Stradiotti, GR Pisaturo, M Noack… - Journal of Hydraulic …, 2025 - ascelibrary.org
The space-and time-averaged velocity profiles in gravel beds show some features that
differentiates them from that established in smooth beds, but the obstruction posed by the …

Sampling variability in estimates of flow characteristics in coarse‐bed channels: Effects of sample size

P Cienciala, MA Hassan - Water Resources Research, 2016 - Wiley Online Library
Adequate description of hydraulic variables based on a sample of field measurements is
challenging in coarse‐bed streams, a consequence of high spatial heterogeneity in flow …