Cáceres, I.

Foti, E.

Hurther, D.

Musumeci, R. E.

Ribberink, J. S.

Sanchez-Arcilla, A.

Sancho, F.

Schimmels, S.

Thorne, P. D.

Van der Werf, J. J.

English

Hydraulic Engineering Repository

Article, Published VersionSanchez-Arcilla, A.; Cáceres, I.; Hurther, D.; Thorne, P. D.; Foti, E.;Musumeci, R. E.; Schimmels, S.; Van der Werf, J. J.; Sancho, F.;Ribberink, J. S.Hydraulic research at the frontier between water andsedimentHydrolinkVerfügbar unter/Available at: https://hdl.handle.net/20.500.11970/109247Vorgeschlagene Zitierweise/Suggested citation:Sanchez-Arcilla, A.; Cáceres, I.; Hurther, D.; Thorne, P. D.; Foti, E.; Musumeci, R. E.;Schimmels, S.; Van der Werf, J. J.; Sancho, F.; Ribberink, J. S. (2014): Hydraulic research atthe frontier between water and sediment. In: Hydrolink 2014/3. Madrid: InternationalAssociation for Hydro-Environment Engineering and Research (IAHR). S. 84-85. https://iahr.oss-accelerate.aliyuncs.com/library/HydroLink/HydroLink2014_03_Hydrolab_IV.pdf.Standardnutzungsbedingungen/Terms of Use:Die Dokumente in HENRY stehen unter der Creative Commons Lizenz CC BY 4.0, sofern keine abweichendenNutzungsbedingungen getroffen wurden. Damit ist sowohl die kommerzielle Nutzung als auch das Teilen, dieWeiterbearbeitung und Speicherung erlaubt. Das Verwenden und das Bearbeiten stehen unter der Bedingung derNamensnennung. Im Einzelfall kann eine restriktivere Lizenz gelten; dann gelten abweichend von den obigenNutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte.Documents in HENRY are made available under the Creative Commons License CC BY 4.0, if no other license isapplicable. Under CC BY 4.0 commercial use and sharing, remixing, transforming, and building upon the materialof the work is permitted. In some cases a different, more restrictive license may apply; if applicable the terms ofthe restrictive license will be binding.84 hydrolink number 3/2014One of the main reasons for this limitation inknowledge is the lack of high resolution obser-vations, particularly under sharp gradients suchas those found in boundary areas.Within the WISE-Hydralab (Water InterfaceSediment Experiment) project we have obtainedsimultaneous and collocated profiles of waterand sediment fluxes and the resulting beddynamics with an unprecedented accuracy. Thecharacterization or the flow field in the horizontaland vertical dimensions has allowed a quanti-tative understanding and even quantification ofsediment transport and entrainment, includingvortex shedding and the bed boundary level.This leads to quantitative estimates of bed andsuspended load, even in the near bed or sheetflow layer.To perform such an analysis we have carriedout a series of identical large scale tests in thewave flumes of Hanover and Barcelona, using anumber of vertical profiles over a horizontaltransect. This has provided quasi 3D resolutionunder controlled laboratory conditions, compa-rable to the level of information usually providedby numerical models, leading to an upgrade ofmobile bed research facilities with informationon water-sediment processes above, within andacross the flow-bed interface.DevelopmentMost available instrumentation does not allowrecovering the sharp variation of sedimentfluxes near the bed boundary nor the pulsingtransport in the alternatively wet and dry swashzone. The novel instruments developed andtested in WISE (figure 1a & b) as part of theHydralab research effort have allowed, for thefirst time, a resolution comparable to that ofadvanced numerical formulations, whose devel-opment had slowed in the last years due to thelimitations of observational equipment.The novel optic and acoustic instrumentation,plus the experimental protocols to recoverreliable and high resolution data, have provideda breakthrough (figure 2) that allows measuringdirectly sheet flow and suspended loads,sediment properties and even the elusive bedlevel. This has resulted in a unique data set attwo complementary large scales supplementedby numerical modelling results. Such a combination of hydraulic and numericalmodelling has allowed an optimization of theexperiments before their execution andguidance support for the equipmentdeployment. The combination of opto-acoustictechniques includes an enhanced stereoscopictechnique for beach topography, includingwater front tracking in the swash zone. It alsofeatures a suspended sediment imagercombined with high resolution acoustic concen-tration and velocity profilers that allow recov-HYDRAULIC RESEARCH AT THE FRONTIER BETWEEN WATER AND SEDIMENTBY A. SANCHEZ-ARCILLA, I. CÁCERES, D. HURTHER, P.D. THORNE, E. FOTI, R.E. MUSUMECI, S. SCHIMMELS, J.J. VAN DER WERF, F. SANCHO, J.S. RIBBERINKSediment transport at land-water boundaries, such as the sea bedor the swash zone, has not yet been adequately solved. Thisapplies to numerical models and to field or lab observations. Andyet these boundary fluxes contribute a non negligible percentage ofthe total sediment transport and cannot be neglected wheneveraccurate and robust predictions are required.Figure 1 - Illustration of the newly developed grid of optic points for the swash zone (a, left panel) and the bed form and suspended load acoustic imager for thenearshore zone (b, right panel)IAHR85hydrolink number 3/2014sediment transport formulations to calculatesediment fluxes as a function of boundary layerstreaming and sediment properties. It has alsoincluded more integrated hydro-morphody-namic models to predict beach evolution for thesimulated hydrodynamics. The results haveallowed validating 3D models (includingadvanced aspects such as sedimententrainment and wave current interactioneffects) and improving the efficiency ofhydraulic models.ConclusionsThe experimental work performed is expectedto contribute to an improved performance ofhydraulic facilities, particularly for mobile bedexperiments in areas that had not beenconsidered before. This includes the swashzone and the near bed sheet flow. The obtainedbenchmark set of data will be also useful forprocess research and numerical modellers,covering aspects such as front trackingering the dynamics of bed levels and forms, aswell as some of the sediment characteristics.The resulting data set provides information onbed plus suspended loads, together with bedforms and their evolution. The experimental workhas also dealt with novel techniques such asferrofluid deformation, with an inductive read outstrategy to recover near bed velocities.ResultsThe WISE results include a benchmark data setwith high resolution hydro/morphodynamicobservations for erosive and accretive waveconditions. The experiments from the Hanoverand Barcelona wave flumes have been designedto reproduce as closely as possible both driversand responses, allowing an assessment of thelimits for facility and instrument performance, aswell as providing valuable insight into thecontrolling processes as a function of scale andenergy levels (figure 3).The numerical modelling has dealt with detailedAugustin Sanchez-Arcilla, Laboratorid Enginyeria Marítima, UniversitatPolitècnica de Catalunya, Barcelona,Spain.Ivan Cáceres, Laboratori d EnginyeriaMarítima, Universitat Politècnica deCatalunya, Barcelona, Spain.David Hurther, Laboratory of Geophysi-cal and Industrial Flows (LEGI), CNRS,Grenoble, France.Peter D. Thorne, National Oceanogra-phy Centre, Liverpool, United Kingdom.Enrico Foti, Department of Civil and Environmental Engineering, Universityof Catania, Catania, Italy.osaria E. Musumeci, Department ofCivil and Environmental Engineering,University of Catania, Catania, Italy. Stefan Schimmels, ForschungszentrumKüste, Leibniz Universitat Hannover,Hannover, Germany.Jebbe J. van der Werf, Deltares, Delft,The Netherlands.Fransisco Sancho, National Civil Engineering Laboratory, LNEC, Lisboa,Portugal. Jan S. Ribberink, Faculty of Engineer-ing, Water Engineering, Management,University of Twente, Enschede, TheNetherlands.Figure 2 - Sample image of the near bed sheet flow layer and the suspended sediment patterns recovered with 1.5mm vertical resolution and sampling at 50HzFigure 3 - Sample result of the intra-wave suspended sediment concentration peaks (left panel, below) as a function of the wave height (left panel above). The aggregated result in terms of profile evolution for accretive wave sequences appears in the right hand panel, showing the limited shoreline recoverytechniques, alternatively wet and dry zones andthe effects of scaling as a function of dominantprocesses. More information can be found in aCoastal Engineering collection of paperspresenting the advances available at the time ofwriting (2011, Coastal Engineering Vol. 16, 7).

Hydraulic research at the frontier between water and sediment

Abstract

Similar works

Full text

Available Versions

Hydraulic Engineering Repository

University of Twente Research Information

NARCIS