Hydrodynamic Equilibrium for Sediment Transport and Bed Response to Wave Motion

Abstract The experiment described was one of the elements of research into sediment transport conducted by the Division of Geotechnics of West-Pomeranian University of Technology. The experimental analyses were performed within the framework of the project “Building a knowledge transfer network on the directions and perspectives of developing wave laboratory and in situ research using innovative research equipment” launched by the Institute of Hydroengineering of the Polish Academy of Sciences in Gdańsk. The objective of the experiment was to determine relations between sediment transport and wave motion parameters and then use the obtained results to modify formulas defining sediment transport in rivers, like Ackers-White formula, by introducing basic parameters of wave motion as the force generating bed material transport. The article presents selected results of the experiment concerning sediment velocity field analysis conducted for different parameters of wave motion. The velocity vectors of particles suspended in water were measured with a Particle Image Velocimetry (PIV) apparatus registering suspended particles in a measurement flume by producing a series of laser pulses and analysing their displacement with a high-sensitivity camera connected to a computer. The article presents velocity fields of suspended bed material particles measured in the longitudinal section of the wave flume and their comparison with water velocity profiles calculated for the definite wave parameters. The results presented will be used in further research for relating parameters essential for the description of monochromatic wave motion to basic sediment transport parameters and „transforming” mean velocity and dynamic velocity in steady motion to mean wave front velocity and dynamic velocity in wave motion for a single wave.

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Modeling of Sediment Transport with a Mobile Mixed-Sand Bed in Wave Motion

Journal of Hydraulic Engineering ◽

10.1061/(asce)hy.1943-7900.0001957 ◽

2022 ◽

Vol 148 (1) ◽

Author(s):

Leszek M. Kaczmarek ◽

Jarosław Biegowski ◽

Łukasz Sobczak

Keyword(s):

Sediment Transport ◽

Wave Motion

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BED LOAD TRANSPORT DUE TO NON-LINEAR WAVE MOTION

Coastal Engineering Proceedings ◽

10.9753/icce.v21.133 ◽

1988 ◽

Vol 1 (21) ◽

pp. 133 ◽

Cited By ~ 1

Author(s):

Hitoshi Tanaka

Keyword(s):

Sediment Transport ◽

Wave Motion ◽

Surf Zone ◽

Function Theory ◽

Transport Rate ◽

Bed Load ◽

Linear Wave ◽

Wave Flume ◽

Load Transport ◽

Bed Load Transport

The bed load transport rate due to wave motion is measured in a wave flume. The modified stream function theory of the author ( Tanaka (1988) ) is applied to the formulation of the sediment transport rate in order to include the non-linearity. The proposed formula predicts well except near the surf zone where the effect of the acceleration plays an important role.

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Boundary Layer under Oscillatory Wave

ISRN Applied Mathematics ◽

10.5402/2011/814045 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8

Author(s):

Mohammad Bagus Adityawan ◽

Hitoshi Tanaka

Keyword(s):

Boundary Layer ◽

Sediment Transport ◽

Turbulent Boundary Layer ◽

Wave Motion ◽

Turbulent Model ◽

Detailed Model ◽

1D Model ◽

Bed Stress ◽

Layer Characteristic ◽

Model Approach

Turbulence due to wave motion and propagation is a very important aspect in sediment transport modeling. The boundary layer characteristic during the process will highly influence the sediment transport mechanism at the bottom. 1D model approach has been widely used to assess the turbulent boundary layer. However, the need for a more detailed model leads to the development of a more sophisticated models. This study presents a 2D turbulent model using k-ω equation to approach the turbulent boundary layer characteristic in oscillatory wave. The equations are solved using finite-difference center scheme. The model is applied to the case of oscillatory sinusoidal and skew wave. The velocity profile and bed stress were compared to those obtained from wind channel experimental data and 1D k-ω model from previous study.

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Numerical Calculations with a Multi-layer Model of Mixed Sand Transport Against Measurements in Wave Motion and Steady Flow

Rocznik Ochrona Środowiska ◽

10.54740/ros.2021.044 ◽

2021 ◽

Vol 23 ◽

pp. 629-641

Author(s):

Leszek M. Kaczmarek

Keyword(s):

Sediment Transport ◽

Steady Flow ◽

Large Scale ◽

Wave Motion ◽

Numerical Calculations ◽

Wave Crest ◽

Sand Transport ◽

Layer Model ◽

Model Concept ◽

Grain Size Distributions

A multi-layer model is used to calculate time-dependent sediment velocity and concentration vertical profiles. This model, in which the differences in sediment transport at different distances from the bed are considered is intended both for the wave motion and steady flow. Numerical calculations were carried out for sediment transport during the wave crest and trough and total sediment transport as a sum of their absolute values. The model concept of variation in shear stress from the skin stress value above the bed to the stress value at the bed previously proposed for steady flow is extended here for the wave motion and verified by direct stress measurements. The calculations were carried out for mixed sand sediments with different grain size distributions including semi-uniform and poorly sorted grains. Comparison with the available small- and large -scale data from flumes and oscillating tunnels yields agreement typically within plus/minus a factor two of measurements.

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SEDIMENT TRANSPORT AND BEACH TRANSFORMATION

Coastal Engineering Proceedings ◽

10.9753/icce.v18.88 ◽

1982 ◽

Vol 1 (18) ◽

pp. 88 ◽

Cited By ~ 1

Author(s):

Tomoya Shibayama ◽

Kiyoshi Horikawa

Keyword(s):

Sediment Transport ◽

Wave Motion ◽

Wave Theory ◽

Linear Wave ◽

Two Dimensional ◽

Beach Profile ◽

Field Investigations ◽

Transport Calculation ◽

Profile Changes ◽

Profile Change

Laboratory and field investigations were performed in order to formulate a predictive model of two-dimensional beach profile change. The observed transport was classified into six types, and transport formulas were deduced for each type based on a microscale description of sediment movement caused by wave action. A numerical model of two-dimensional beach transformation was then developed. Beach profile changes calculated with the model were then compared with the laboratory results. The model was found to give reasonable results except in the vicinity of the wave plunging point. The sediment transport calculation is based on a sinusoidal velocity profile. The model appeares to give good results as long as the wave motion can be reasonably approximated by linear wave theory.

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Influence of Wave Shape on Sediment Transport in Coastal Regions

Archives of Hydro-Engineering and Environmental Mechanics ◽

10.1515/heem-2018-0006 ◽

2018 ◽

Vol 65 (2) ◽

pp. 73-90 ◽

Cited By ~ 1

Author(s):

Rafał Ostrowski

Keyword(s):

Sediment Transport ◽

Water Surface ◽

Wave Motion ◽

Free Stream ◽

Theoretical Description ◽

Wave Shape ◽

Coastal Regions ◽

Current Impact ◽

Wave Induced ◽

Asymmetric Wave

AbstractThe paper deals with the influence of the wave shape, represented by water surface elevations and wave-induced nearbed velocities, on sediment transport under joint wave-current impact. The focus is on the theoretical description of vertically asymmetric wave motion and the effects of wave asymmetry on net sediment transport rates during interaction of coastal steady currents, namely wave-driven currents, with wave-induced unsteady free stream velocities. The cross-shore sediment transport is shown to depend on wave asymmetry not only quantitatively (in terms of rate), but also qualitatively (in terms of direction). Within longshore lithodynamics, wave asymmetry appears to have a significant effect on the net sediment transport rate.

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PRACTICAL SCALING OF COASTAL MODELS

Coastal Engineering Proceedings ◽

10.9753/icce.v14.121 ◽

1974 ◽

Vol 1 (14) ◽

pp. 121

Author(s):

J.W. Kamphuis

Keyword(s):

Sediment Transport ◽

Theoretical Approach ◽

Wave Motion ◽

Scale Effects ◽

Fixed Bed ◽

Mobile Bed ◽

Long Wave ◽

Motion Time ◽

Practical Design ◽

Basic Scale

In this paper the practical design of coastal mobile bed models is considered. The semi-theoretical approach expressed by the author in earlier publications (9,10,11,12) is extended and used to classify and design coastal models. Fixed bed coastal models are discussed first to form a basis for the argument. Subsequently, mobile bed models are classified according to criteria of dynamic similarity satisfied in their design and scale effects present in their operation. Basic scale laws are next derived for all classifications of coastal models. This is done for both inshore and offshore models, the distinction being brought about by adjusting the velocity scales for unidirectional (and long wave) motion. Time and sediment transport scales are next derived and some well known models are compared. The presence of bedform and model distortion is also treated. The work is compared with that of other authors.

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