Download or read book Analysis of Overwash Sediment Transport in an Experimental Laboratory Setting Channel Dimension Influence on Washover Deposits written by Madison Lynn Heffentrager and published by . This book was released on 2021 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Artificial dunes and other human-made solutions in coastal areas often result in changes to coastal hydraulics and sediment transport, which can lead to changes in long-term evolution of coastal landforms and places communities and other coastal infrastructure at risk from coastal hazards. Recent large-scale restoration projects have shown some success in restoring dynamic coastal processes while increasing habitat in built-dune environments. While there are initial successes, further research is required to: understand the dimensions of change needed to sustain the necessary coastal dynamics; determine the types of approaches to attain a resilient and functioning system and generate reproducible results that will support various coastal management approaches. In this thesis study, throat-dimensions (referred to also as channel dimensions) that induce washover formation are varied in a physical laboratory environment to examine overwash sediment transport and deposition. Uniform initial channels (multiple channel dimensions tested throughout experiment) are emplaced in an artificial sand barrier that serves as a physical representation of a barrier island within an experimental table. The experimental set-up comprises of an ocean-side that is filled at a constant infill rate to overtop the sand barrier, which induces overwash and resulting observed washover features. This experimental set-up was inspired and compared to a similar study observing overwash in an experimental setting. In this study, the methods from previous works were expanded to analyze different channel dimensions. The different channel dimensions mark different experimental runs, hereby referred to as scenarios. Each various channel scenario is repeated over five replicated trials to ensure that the observed results are not due to chance. Each trial is captured with a nadir-view camera, where the trials are video recorded and images from the video are extracted and resulting features are measured within ImageJ. Narrow, deep channels generally produced shorter washover deposits with smaller areas. Shallow, wider channels, or no channels incised, produced washover deposits with generally longer lengths and larger areas. The study results can aid in understanding how human-influenced systems can be altered to restore dynamic coastal processes and barrier island evolutionary pathways.
Download or read book An Experimental Setup for the Study of Sediment Transport in Nonsteady Flow written by Farouk M. Abdel-Aal and published by . This book was released on 1971 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sedimentation and Hydrodynamics Study of U S Coast Guard Station Boat Basin Port Huron Michigan written by Robert R. Bottin and published by . This book was released on 1999 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stream Channel Stability written by Joe C. Willis and published by . This book was released on 1981 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a stable alluvial channel, no net erosion or deposition of sediment occurs on the average. The sediment supply rate from upstream is balanced by capacity of the flow to transport the bed material. Any successful channel design must maintain this equilibrium or establish it for channel reaches that are not stable. Design relationships between the bed material transport capacity and the hydraulic variables of flow are based primarily on data from relatively small test channels. Reliable data for equilibrium transport of bed material by flows over about twenty cfs are not adequate to insure that data from small flumes can be extrapolated to prototype designs. An investigation was conducted in the 250-ft long test channel at the USDA Sedimentation Laboratory to obtain additional data on equilibrium transport by flows up to 150 cfs. Data on the transport rates, flow friction factors, and statistical properties of the bed forms were obtained. The results are presented as basic variable correlations with the controlled variables of the experiments, depth and discharge, along with attempts to generalize the relationships by similitude principles. (Author).
Download or read book Open channel Flow Through Simulated Vegetation written by Fabian Lopez and published by . This book was released on 1997 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Discharge Ratio and Junction Angle on Sediment Transport and Deposition Patterns in Open Channel Confluences written by Qingcheng Yu and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Open channel confluences are common geographical structures in surface runoff. Most natural rivers originate from mountains and hills, flow into a main stream at confluences and finally head into the sea. Confluences are major sites for a main stream to obtain sediment and water from a tributary. Complex turbulence structures such as vortices, flow stagnation, secondary flow, flow re-circulation and water exchange both in vertical and lateral directions result in complicated sedimentation, erosion, mixing and contaminant transport at open channel confluences. The detailed study of flow dynamics and morphodynamics in confluences is of great significance to the urban flood control, scour of the river bed, design and maintenance of the channel and sediment and pollutants transport. This thesis describes a novel flume experiment on the sediment transport patterns in channel confluences as a function of different flow and geometry conditions. The initial equilibrium bed geometry was developed in a mobile bed confluence flume under four cases including two junction angles and two discharge ratios. The equilibrium bed was fixed for each case allowing for detailed flow velocimetry. The observed spatial patterns of turbulence statistics are evaluated with respect to the equilibrium bathymetry. Sediment were then fed instantaneously to the tributary channel at three different feeding sites in order to study the sediment deposition patterns. It was observed that although the sediment initiated at different feeding sites move along different paths through the confluence, all sediment tend to deposit at the face of the dune in the flow separation zone. This thesis also investigated how the deposition pattern would change versus time when feeding at the same site from the tributary channel. The time history of deposition pattern was also investigated for one of the cases. The sediment that initially deposit at the face of the dune eventually moved to the back of the dune and deposit around the post-confluence scour hole, demonstrating that over time the deposition pattern evolves to a state which is similar with the original bed morphology.
Download or read book Turbulence and Flow Sediment Interactions in Open Channel Flows written by Roberto Gaudio and published by MDPI. This book was released on 2021-06-04 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main focus of this Special Issue of Water is the state-of-the-art and recent research on turbulence and flow–sediment interactions in open-channel flows. Our knowledge of river hydraulics is deepening, thanks to both laboratory/field experiments related to the characteristics of turbulence and their link to erosion, transport, deposition, and local scouring phenomena. Collaboration among engineers, physicists, and other experts is increasing and furnishing new inter-/multidisciplinary perspectives to the research of river hydraulics and fluid mechanics. At the same time, the development of both sophisticated laboratory instrumentation and computing skills is giving rise to excellent experimental–numerical comparative studies. Thus, this Special Issue, with ten papers by researchers from many institutions around the world, aims at offering a modern panoramic view on all the above aspects to the vast audience of river researchers.
Download or read book Application of Channel Stability Methods written by Ronald R. Copeland and published by . This book was released on 1994 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stream Bank Stability written by Tsu-Yi Su and published by . This book was released on 1981 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Dam Removal written by David T. Williams and published by . This book was released on 1977 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of Transportation of Fine Sediments by Flowing Water written by Anton Adam Kalinske and published by . This book was released on 2013-03 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow and Sediment Transport in Compound Channels written by S. Ikeda and published by CRC Press. This book was released on 2009-07-01 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph provides a comprehensive state-of-the-art description of the work carried out in the UK and Japan on "Flow and Sediment Transport in Compound Channels". It therefore describes research which has been conducted, primarily over the last two decades, and which has yielded a fairly detailed picture of the important behaviours of compound channels and produced a number of engineering prediction methods which ought to be widely adopted in practice. The text will inevitably highlight areas where our knowledge is sparse and it will spur others on in the task of filling in such gaps. The concept of bi-national groups of researchers meeting together intermittently over period of some years, though not new, has drawn both inspiration and experience and the interaction has produced tangible outcomes in the form of this useful publication.
Download or read book General Study of the Modified Einstein Method of Computing Total Sediment Discharge written by D. E. Burkham and published by . This book was released on 1980 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sediment Control at Intakes written by Pauline Avery and published by Air Science Company. This book was released on 1989 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Channel Depth as a Factor in Estuarine Sedimentation written by Henry B. Simmons and published by . This book was released on 1965 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stream Channel Stability written by Carlos V. Alonso and published by . This book was released on 1981 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study is to develop a better understanding of the stochastic structure of the instantaneous boundary shear processes in open channel flows. This report presents new measurements of some stochastic properties of boundary shear stress taken at points spaced over half the wetted perimeter of a smooth open channel, under conditions of essentially constant aspect ratio and Reynolds number. The instantaneous boundary shear stress was measured with hot-film sensors driven by constant-temperature anemometers. The anemometer signals were digitized and analyzed in a high speed computer. The effects of position along the wetted perimeter on the statistical moments and the probabilistic distribution of the instantaneous boundary shear stress are discussed. (Author).
Download or read book Hydrodynamics and Sediment Transport at the River ocean Interface written by Anthony Poggioli and published by . This book was released on 2015 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study presents a combination of numerical and analytical investigations of fluid and sediment transport mechanics through the river-ocean interface. This region is defined broadly as the region within the river that is influenced by the receiving basin--both the salinity and the oscillating and mean basin heights--as well as the portion of the river influenced by the presence of a distinct fluvial buoyant water mass. More narrowly, we consider in this study an atidal salt wedge, the upstream hydraulic transition zone in the unstratified river, and the near-field river plume. The first main chapter presents a hydraulic model of the salt wedge estuary in sloped and landward-converging channels. It is found that the non-dimensionalized intrusion length is a function of the freshwater Froude number, as noted in previous studies, as well as new parameters describing the channel geometry. Further, it is found that the primary geometric influence on the intrusion length is the channel bottom slope. Comparison to field data is given indicating that the influence of nonzero bottom slope may account for the discrepancy between observation and the canonical flat estuary theory (Schijf & Schönfeld 1953). Next, we link our hydraulic model of the salt wedge to a hydraulic model of the upstream river transition zone, which is influenced by the depth of the receiving basin and is not in normal flow. We add to this a parameterization of total sediment transport in the unstratified river (Engelund & Hansen 1967) and a newly developed hydraulic model of sediment transport in the salt wedge. The model retains the key mechanistic features of sediment transport in highly stratified estuaries and is ideal for morphodynamic applications. We find that the principle influence of the salt wedge is an increase in net deposition in the lower river and the introduction of a secondary maximum aggradation length scale in addition to the backwater length discussed in Chatanantavet et al. (2012). Finally, we present experimental simulations of the steady state estuary and river plume. The results of the estuary experiments quantify the influence of bottom slope on the reduction of sensitivity of intrusion length to river discharge and confirm the results of the hydraulic model. The plume experiments indicate that the plume transitions to a jet-like outflow for sufficiently large values of Ff in which the spreading rate is determined by lateral entrainment instead of the plume buoyancy and the liftoff is pushed far offshore. This transition is not gradual but rather step-like, being concentrated on one value (or a narrow band of values of) Ff. Both this critical value of Ff and the jet spreading rate depend crucially on the plume inflow aspect ratio. This jet-like behavior is anticipated to have crucial implications for delta progradation processes and the magnitude of sediment erosion in the lower river during flood events.
