Data of boulder transport experiment in super-large wave flume

The rapid growth of marine aquaculture around the world accentuates issues of sustainability and environmental impacts of large-scale farming systems. One potential mitigation strategy is to relocate to more energetic offshore locations. However, research regarding the forces which waves and currents impose on aquaculture structures in such conditions is still scarce. The present study aimed at extending the knowledge related to live blue mussels (Mytilus edulis), cultivated on dropper lines, by unique, large-scale laboratory experiments in the Large Wave Flume of the Coastal Research Center in Hannover, Germany. Nine-months-old live dropper lines and a surrogate of 2.0 m length each are exposed to regular waves with wave heights between 0.2 and 1.0 m and periods between 1.5 and 8.0 s. Force time histories are recorded to investigate the inertia and drag characteristics of live mussel and surrogate dropper lines. The surrogate dropper line was developed from 3D scans of blue mussel dropper lines, using the surface descriptor Abbott–Firestone Curve as quality parameter. Pull-off tests of individual mussels are conducted that reveal maximum attachment strength ranges of 0.48 to 10.55 N for mussels that had medium 3.04 cm length, 1.60 cm height and 1.25 cm width. Mean drag coefficients of CD = 3.9 were found for live blue mussel lines and CD = 3.4 for the surrogate model, for conditions of Keulegan–Carpenter number (KC) 10 to 380, using regular wave tests.

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Experimental Study on Sediment Transport in Surf and Swash Zones Using Large Wave Flume

Coastal Engineering 1996 ◽

10.1061/9780784402429.238 ◽

1997 ◽

Author(s):

Takao Shimizu ◽

Masaaki Ikeno

Keyword(s):

Experimental Study ◽

Sediment Transport ◽

Large Wave ◽

Wave Flume

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EXPERIMENTS ON BEACH PROFILE CHANGE WITH A LARGE WAVE FLUME

Coastal Engineering Proceedings ◽

10.9753/icce.v18.85 ◽

1982 ◽

Vol 1 (18) ◽

pp. 85 ◽

Cited By ~ 3

Author(s):

Ryoichi Kajima ◽

Takao Shimizu ◽

Kohki Maruyama ◽

Shozo Saito

Keyword(s):

Simple Model ◽

Transport Rate ◽

Sand Transport ◽

Two Dimensional ◽

Beach Profile ◽

Large Wave ◽

Wave Flume ◽

Grain Sizes ◽

Profile Changes ◽

Profile Change

Two-dimensional beach profile changes were investigated with a newly constructed prototype-scale wave flume. The flume is 205 m long, 3.4 m wide and 6 m deep. Sand of two grain sizes was used in the experiments. Analysis of the results was made through use of the parameter C, introduced by Sunamura and Horikawa (1974) to classify beaches as either erosional and accretionary. Beach profile changes obtained in the flume were similar to those in the prototype (field). Net sand transport rate distributions were classified into five types, two of which do not seem to have been observed in laboratory (smallscale) experiments. A simple model describing the five types was developed for evaluating two-dimensional beach profile changes.

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Nonlinear and Dissipative Characteristics of a Combined Random-Cnoidal Wave Field

Volume 7A: Ocean Engineering ◽

10.1115/omae2017-62634 ◽

2017 ◽

Author(s):

James M. Kaihatu ◽

John T. Goertz ◽

Samira Ardani ◽

Alex Sheremet

Keyword(s):

Wave Spectrum ◽

Leading Edge ◽

Dissipation Function ◽

Indian Ocean Tsunami ◽

Random Wave ◽

Cnoidal Wave ◽

State University ◽

Large Wave ◽

Wave Flume ◽

Wave Trains

Images of the 2004 Indian Ocean tsunami at landfall shows a leading edge marked by short waves (“fission” waves). These waves appear to be cnoidal in shape and of a temporal and spatial scale in line with the longest swell present in the region, and may interact with the longer waves in the background random wave spectrum. As part of a comprehensive series of experiments, the Large Wave Flume at Oregon State University (USA) was used to generate and measure the properties of cnoidal, random, and combined cnoidal-random wave trains. Both the nonlinear energy transfer characteristics (via bispectral analysis) and dissipation characteristics (via a proxy dissipation function) are studied for all generated wave conditions. It is generally determined that the characteristics of the cnoidal wave dominate the combined cnoidal-random wave signals if the energy of the cnoidal wave is at least equal to that of the random wave.

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WAVE RUN-UP OBSERVATIONS ON REVETMENTS WITH DIFFERENT POROSITIES

Coastal Engineering Proceedings ◽

10.9753/icce.v33.structures.73 ◽

2012 ◽

Vol 1 (33) ◽

pp. 73 ◽

Cited By ~ 2

Author(s):

Stefan Schimmels ◽

Michalis Vousdoukas ◽

Dagmara Wziatek ◽

Katharina Becker ◽

Fabian Gier ◽

...

Keyword(s):

Data Analysis ◽

Concrete Block ◽

Video Data ◽

Coastal Protection ◽

Large Wave ◽

Wave Flume ◽

New Type ◽

Run Up ◽

Highly Porous ◽

Good Agreement

Wave run-up plays an important role in the design of coastal protection structures. However, none of the existing formulae for wave run-up predictions explicitly considers the effect of revetment porosity. Recently, two revetments have been tested in the Large Wave Flume (GWK) of Forschungszentrum Küste (FZK), a new type of highly porous polyurethane bonded (PBA revetment) revetment and a smooth interlocked pattern placed concrete block revetment (IPPB revetment), which is considered as “weakly permeable” for the present study. Wave run-up is evaluated by video data analysis based on timestack image processing. The results derived from the timestacks are compared to run-up data measured with conventional wire gauges and the good agreement demonstrates the accuracy and reliability of the video data analysis. The effect of the porosity of the revetment is incorporated into the EuroTop wave run-up formula, showing that for the present case it may reduce the relative run-up heights Ru,2%/Hm0 by about 25 % to 50 % as compared to a smooth impermeable slope.

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BREAKING AND WASH UP OF SOLITARY WAVES ON A COMPOSITE BEACH

Coastal Engineering Proceedings ◽

10.9753/icce.v36v.waves.29 ◽

2020 ◽

pp. 29

Author(s):

Hajo von Hafen ◽

Jacob Stolle ◽

Nils Goseberg ◽

Ioan Nistor

Keyword(s):

Solitary Waves ◽

Horizontal Plane ◽

Large Scale ◽

Propagation Path ◽

Rock Falls ◽

Damage Potential ◽

Large Wave ◽

Beach Slope ◽

Wave Flume ◽

Run Up

Hazardous events, such as landslides, rock slides, rock falls or avalanches often generate extreme, impulsive waves when entering water bodies (Fuchs & Hager, 2015). These waves are approximated by solitary waves and researchers investigate their damage potential when inundating built environment. Deepening the understanding of solitary waves running up a uniform beach slope and propagating over a subsequent horizontal plane can help to reduce and mitigate damage and the number of casualties caused by such a hazardous event. So far, few authors addressed this specific setting near-shore (Fuchs & Hager, 2015; Zelt & Raichlen, 1991). In this study, large scale solitary waves propagate about 200 m in in the Large-Wave Flume (GWK, 307 m 5 m 7 m) at the Coastal Research Center in Hannover, Germany then they run up a beach slope and subsequently break, generating a bore which advances onto a subsequent, initially dry, horizontal surface. Unlike previous studies, the generated solitary waves broke close to the edge between the beach slope and the horizontal plane section. The overall aim of this study is to investigate the characteristics of the broken waves' dynamics. In addition, their surge profile and front celerity are compared to those of the non-breaking solitary waves. Subsequently, the differences between the velocity regimes along the bore propagation path are presented and linked to the fundamental physical processes behind.

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LOADING OF VERTICAL WALLS BY OVERTOPPING BORES USING PRESSURE AND FORCE SENSORS - A LARGE SCALE MODEL STUDY

Coastal Engineering Proceedings ◽

10.9753/icce.v33.currents.44 ◽

2012 ◽

Vol 1 (33) ◽

pp. 44 ◽

Cited By ~ 2

Author(s):

Karunya Ramachandran ◽

Rebeca Roldan Genzalez ◽

Hocine Oumeraci ◽

Stefan Schimmels ◽

Matthias Kudella ◽

...

Keyword(s):

Large Scale ◽

Vertical Wall ◽

Pressure Sensors ◽

Scale Model ◽

Force Sensors ◽

Research Project ◽

Joint Research ◽

Large Wave ◽

Wave Flume ◽

Joint Research Project

This study is based on the data obtained from tests carried out in the Large Wave Flume (Grosser Wellenkanal (GWK)) in Hannover in the frame of a joint research project of Ghent University (Belgium) and Forschungszentrum Küste (FZK, Germany). The goal of the research project is to determine the wave induced loads on vertical storm walls located at the end of overtopped dike, which are designed to protect coastal cities from overtopping and floods. The loads resulting from waves overtopping the dike and impacting the vertical wall as a bore are measured by means of both force and pressure sensors. This paper describes the results of pressure and force records at the vertical wall, including a comparative analysis of the overall forces obtained by pressure integration and force sensors for two different wall setups: Fully blocked wall and partially blocked wall.

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SHOREWARD SAND TRANSPORT OUTSIDE THE SURFZONE, NORTHERN GOLD COAST, AUSTRALIA

Coastal Engineering Proceedings ◽

10.9753/icce.v33.sediment.26 ◽

2012 ◽

Vol 1 (33) ◽

pp. 26 ◽

Cited By ~ 2

Author(s):

Dean Patterson

Keyword(s):

Surf Zone ◽

River Mouth ◽

Transport Processes ◽

Gold Coast ◽

Sand Transport ◽

Large Wave ◽

Wave Flume ◽

Shoreline Evolution ◽

The One

To date, no suitable theoretical basis has been derived to predict with reliable accuracy the shoreward sand transport under waves in the deeper water outside the surf zone. This is important for understanding the rate of recovery of beaches after major storm erosion and, in some circumstances, to quantify net shoreward supply of sand to the shoreline from the active lower shore-face below the depth of storm erosion bar development. Even a relatively low rate of long term shoreward net supply may contribute to shoreline stability where it offsets a gradient in the longshore sand transport that would otherwise lead to recession. This paper outlines the results of analysis of a 41 year dataset of beach and nearshore profile surveys to quantify annual average rates of shoreward net sand transport in 6-20m water in an area where the profiles are not in equilibrium due to the existence of a residual river mouth ebb delta bar lobe. Additionally, an empirical adaptation of the sheet flow relationship of Ribberink and Al-Salem (1990) to provide for the effects of ripples has been derived from large wave flume data and correlates well with the measured Gold Coast transport rates. These have been applied to a new coastline modelling system developed as part of research into the long term evolution of Australia’s central east coast region in response to sea level change and longshore sand transport processes, which combines the one-line concept of shoreline profile translation within the zone of littoral sand transport with cross-shore profile evolution across the deeper shore-face profile below that zone. It demonstrates the importance of providing for both the shoreward supply from the continental shelf and the varying profile response time-scale across the shore-face in predicting shoreline evolution.

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