Flow dynamics and mixing processes in hydraulic jump arrays: Implications for channel-lobe transition zones

2016-11-01
Dorrell, R. M.
Peakall, J.
Sumner, E. J.
Parsons, D. R.
Darby, S. E.
Wynn, R. B.
Ozsoy, E.
Tezcan, Devrim
Show full item record
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
235
views
148
downloads
A detailed field investigation of a saline gravity current in the southwest Black Sea has enabled the first complete analysis of three-dimensional flow structure and dynamics of a series of linked hydraulic jumps in,stratified, density-driven, flows. These field observations were collected using an acoustic Doppler current profiler mounted on an autonomous underwater vehicle, and reveal that internal mixing processes in hydraulic jumps, including flow expansion and recirculation, provide a previously unrecognised mechanism for grain-size sorting and segregation in stratified density-driven flows. Field observations suggest a newly identified type of hydraulic jump, that is a stratified low Froude number (<1.5-2) subaqueous hydraulic jump, with an enhanced ability to transport sediment downstream of the jump, in comparison to hydraulic jumps in other subaerial and submarine flows. These novel field data underpin a new process-based conceptual model of channel lobe transition zones (CLTZs) that explains the scattered offset nature of scours within such settings, the temporal variations in infill and erosion between adjacent scours, how bed shear stresses are maintained across the CLTZ, and why the locus of deposition is so far downstream of the scour zone. (C) 2016 The Authors. Published by Elsevier B.V.
Gravity currents, Hydraulic jumps, Stratification, Channel-lobe transition zone, DEEP-SEA FAN, TURBIDITY CURRENTS, CYCLIC STEPS, CONTINENTAL-SHELF, BOSPORUS STRAIT, MARMARA SEA, EVOLUTION, DEPOSITS, MORPHOLOGY, DRIVEN
https://hdl.handle.net/11511/31351
Graduate School of Marine Sciences, Article

Suggestions

Generation of surface waves due to sudden movements at the sea bottom
Kırlangıç, Özgür Ulaş; Aydın, İsmail; Department of Civil Engineering (2004)
A mathematical model is developed for investigating time dependent surface deformations of a hydrostatic water volume, when it is subjected to a sudden partial collapse or rise of the sea bottom. The model solves two-dimensional Navier-Stokes Equations on a vertical plane numerically by using Marker and Cell Method (MAC) for viscous and compressible fluid including all the nonlinear effects in the solution. For demonstration, a vertical motion was given to a section in a hypothetical reservoir bed within a ...
Seismic assessment of a monolithic RCC gravity dam including three dimensional dam-foundation-reservoir interaction
Yilmazturk, Sema Melek; Arıcı, Yalın; Binici, Barış (2015-10-01)
In this study, the seismic response of a tall roller compacted concrete gravity dam located in a highly seismic zone is investigated. The response of this monolithic RCC gravity dam is examined by conducting analyses including three dimensional dam-reservoir-foundation interaction. The effect of the foundation/structure moduli ratio, material damping, and bottom absorption and reservoir compressibility on the performance of the dam were investigated. Selection of an optimal downstream slope was discussed ba...
Simulation of surface waves generated by a rapid rise of a block at the sea bottom
Şenol, Nalan; Aydın, İsmail; Department of Civil Engineering (2005)
A mathematical model is developed for investigating time dependent surface deformations of a hydrostatic water volume, when it is subjected to a sudden partial rise of the sea bottom. In the model, 2-dimensional, compressible, and viscous Navier-Stokes equations are solved by Marker and Cell (MAC) method. Variable mesh size in both horizontal and vertical directions with a staggered grid arrangement is used. Limited compressibility model is utilized for pressure. Various computational tests are done for the...
Seismic testing of a scaled roller-compacted-concrete gravity dam
Gharibdoust, Ali; Binici, Barış; Department of Civil Engineering (2016)
Within the last half-century, seismic response analysis of concrete gravity dams has been extensively studied. Studies reveal that two types of failure modes prevail in the form of dam body cracking or base slide. The literature lacks the conditions that clearly differentiate the two failure types. In this context a state of the art single degree of freedom pseudo-dynamic testing was developed to assess the gravity dam response on smooth foundation interface. Three different hazard levels of earthquake name...
Earthquake stresses and effective damping in concrete gravity dams
Akpinar, Ugur; Binici, Barış; Arıcı, Yalın (2014-03-01)
Dynamic analyses for a suite of ground of motions were conducted on concrete gravity dam sections to examine the earthquake induced stresses and effective damping. For this purpose, frequency domain methods that rigorously incorporate dam-reservoir-foundation interaction and time domain methods with approximate hydrodynamic foundation interaction effects were employed. The maximum principal tensile stresses and their distribution at the dam base, which are important parameters for concrete dam design, were ...
Citation Formats
R. M. Dorrell et al., “Flow dynamics and mixing processes in hydraulic jump arrays: Implications for channel-lobe transition zones,” MARINE GEOLOGY, pp. 181–193, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31351.
METU IIS - Integrated Information Service open@metu.edu.tr