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91	Investigation Of Hydrodynamic Demands Of Tsunamis In Inundation Zone Ozer, Ceren 01 February 2007 (has links) (PDF) This thesis analyzed the new parameter hydrodynamic demand representing the damage of tsunami waves on structures and coastlines,maximum positive amplitudes and current velocities occurred during tsunami inundation by using the numerical model TUNAMI-N2. Regular shaped basins were used with two different bottom slopes in analyses in order to understand the behaviour of tsunami wave and investigate the change of important tsunami parameters along different slopes during tsunami inundation. In application, different initial conditions were used for wave profiles such as solitary wave, leading elevation single sinusoidal wave and leading depression sinusoidal wave. Three different initial wave amplitudes were used in order to test the change of distribution of the hydrodynamic demand. The numerical results were compared and discussed with each other and with the results of existing analytical and experimental studies.
92	Statistical And Spatial Approaches To Marina Master Plan For Turkey Karanci, Ayse 01 February 2011 (has links) (PDF) Turkey, with its climate, protected bays, cultural and environmental resources is an ideal place for yacht tourism. Subsequently, yacht tourism is increasing consistently. Yacht tourism can cause unmitigated development and environmental concerns when aiming to achieve tourist satisfaction. As the demand for yacht tourism intensifies, sustainable development strategies are needed to maximize natural, cultural and economic benefits. Integration of forecasts to the strategic planning is necessary for sustainable and use of the coastal resources. In this study two different quantitative forecasting techniques - Exponential smoothing and Auto-Regressive Integrated Moving Average (ARIMA) methods were used to estimate the demand for yacht berthing capacity demand till 2030 in Turkey. Based on environmental, socio-economic and geographic data and the opinions gathered from stakeholders such as marina operators, local communities and government officials an allocation model was developed for the successful allocation of the predicted demand seeking social and economical growth while preserving the coastal environment. AHP was used to identify and evaluate the development, social and environmental and geographic priorities. Aiming a dynamic plan which is responsive to both national and international developments in yacht tourism, potential investment areas were determined for the investments required to accommodate the future demand. This study provides a multi dimensioned point of view to planning problem and highlights the need for sustainable and dynamic planning at delicate and high demand areas such as coasts.
93	Tsunami Hydrodynamics In Coastal Zones Ozer, Ceren 01 June 2012 (has links) (PDF) This study analyzes the parameter &ldquo / hydrodynamic demand&rdquo / that is also defined by the square of Froude Number representing the damage of tsunami waves on structures and coastlines, and other hydrodynamic parameters, i.e., the distribution of instantaneous flow depths, runup values and the direction of maximum currents, occurred during tsunami inundation by using advanced numerical modeling. The analyses are performed on regular-shaped basins with different bottom slopes and real-shaped topographies using different wave shapes, wave periods and types. Various orientation and amount of coastal and land structures are used in simulations to have results for many different cases. This study provides the opportunity to define the damage of level in residential areas and to test the performance of coastal protection structures. The behavior of tsunami hydrodynamic parameters in shallow and inundation zone is investigated and a correlation is obtained between the average maximum values of square of Froude Number with the wave characteristics and sea bottom slope. After determining hydrodynamic parameters in regular shaped basins, a case study is applied by modeling the March 11, 2011 Great East Japan Tsunami with finer resolution in nested domains. The determination of hydrodynamic parameters in inundation zone during 2011 Japan event is performed in one of the most damaged coastal city Kamaishi.
94	Hydrodynamics of ducted and open-centre tidal turbines Belloni, Clarissa S. K. January 2013 (has links) This study presents a numerical investigation of ducted tidal turbines, employing three-dimensional Reynolds-averaged Navier-Stokes simulations. Bidirectional ducted turbines are modelled with and without aperture, referred to as ducted and open- centre turbines respectively. The work consists of two investigations. In the first, the turbine rotors are represented by actuator discs, a simplification which captures changes in linear momentum and thus the primary interaction of the turbine with the flow through and around the duct, while greatly reducing computational complexity. In the second investigation, the turbine rotors are represented through a CFD-integrated blade element momentum model, employing realistic rotor data, capturing swirl and blade drag in addition to the extraction of linear momentum. Both modelling techniques were employed to investigate the performances of bare, ducted, and open-centre turbines, relating these to the flow fields exhibited. For axial flow, substantial decreases in power generated by the ducted and open-centre turbines were found, relative to a bare turbine of equal total device diameter. For open-centre turbines, an increase in aperture size leads to a further reduction in power generated. Increased blockage was shown to positively affect the performance of all devices. Two further measures of performance were employed: power density, normalising the power by the rotor area, and basin efficiency, relating the power generated to the overall power removed from the flow. Moderate increases in power density can be achieved for the ducted and open-centre devices, while their basin efficiencies are of similar value to that of the bare turbine. For yawed inflow, the performance of the bare turbine decreases, whilst that of the ducted and open-centre turbines increases. This is due to an increased flow velocity following flow acceleration around the inlet lip of the duct and also an increase in effective blockage as ducts present greater projected frontal area when approached non-axially. 621.2
95	A preliminary analysis of the sediment budget across the Swartvlei estuary mouth Roets, Adriaan 12 1900 (has links) Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The Swartvlei estuary and lake system is situated on the southern coast of the Western Cape Province of South Africa and forms part of the core conservation area of the Wilderness National Park. The Swartvlei system comprises two interlinked water bodies, namely Swartvlei Lake and Swartvlei estuary. SANParks have been monitoring this estuary closely over the past two decades, due to its importance to the ecology and to tourism. There are also low-lying properties on the perimeter of the Swartvlei estuary which run the risk of occasional flooding. Two of the major monitoring issues in this estuary system are the water level required for successful mouth breaching, and the influence of the water level on the low-lying properties. This study presents a preliminary analysis of the sediment budget across the Swartvlei estuary mouth. The objective of this study was to identify the various sediment contributory factors and to estimate the quantities that each individually contributed towards the defined sediment budget. / AFRIKAANSE OPSOMMING: Die Swartvlei meer en see monding is geleë aan die kaapse suidkus van Suid- Afrika. Dit vorm deel van die kern bewarings area van die Wilderness Nationale Park. Die Swartvlei sisteem bestaan uit twee verbinde, kern dele nl: Swartvlei meer en estuarium. Vir die afgelope twee dekades is hierdie area onder die noue toesig van SANParke as gevolg van die belangrikheid van die area met betrekking tot toerisme en ekologie. Daar is ook menigde laag liggende eiendomme aan die oewers, wat baie sensitief is vir watervlak stygings. Die optimum water vlakke benodig vir die uitskuring van die gety monding het ook implikasies vir die laag liggende eiendome en vereis noukeurige monitering. ‘n Voorlopige analise van die sediment begroting rondom die gety monding word deur hierdie studie voorgelê. Coastal Engineering, Sediment budget Theses -- Civil engineering Dissertations -- Civil engineering Eolian processes UCTD
96	A high order Discontinuous Galerkin - Fourier incompressible 3D Navier-Stokes solver with rotating sliding meshes for simulating cross-flow turbines Ferrer, Esteban January 2012 (has links) This thesis details the development, verification and validation of an unsteady unstructured high order (≥ 3) h/p Discontinuous Galerkin - Fourier solver for the incompressible Navier-Stokes equations on static and rotating meshes in two and three dimensions. This general purpose solver is used to provide insight into cross-flow (wind or tidal) turbine physical phenomena. Simulation of this type of turbine for renewable energy generation needs to account for the rotational motion of the blades with respect to the fixed environment. This rotational motion implies azimuthal changes in blade aero/hydro-dynamics that result in complex flow phenomena such as stalled flows, vortex shedding and blade-vortex interactions. Simulation of these flow features necessitates the use of a high order code exhibiting low numerical errors. This thesis presents the development of such a high order solver, which has been conceived and implemented from scratch by the author during his doctoral work. To account for the relative mesh motion, the incompressible Navier-Stokes equations are written in arbitrary Lagrangian-Eulerian form and a non-conformal Discontinuous Galerkin (DG) formulation (i.e. Symmetric Interior Penalty Galerkin) is used for spatial discretisation. The DG method, together with a novel sliding mesh technique, allows direct linking of rotating and static meshes through the numerical fluxes. This technique shows spectral accuracy and no degradation of temporal convergence rates if rotational motion is applied to a region of the mesh. In addition, analytical mappings are introduced to account for curved external boundaries representing circular shapes and NACA foils. To simulate 3D flows, the 2D DG solver is parallelised and extended using Fourier series. This extension allows for laminar and turbulent regimes to be simulated through Direct Numerical Simulation and Large Eddy Simulation (LES) type approaches. Two LES methodologies are proposed. Various 2D and 3D cases are presented for laminar and turbulent regimes. Among others, solutions for: Stokes flows, the Taylor vortex problem, flows around square and circular cylinders, flows around static and rotating NACA foils and flows through rotating cross-flow turbines, are presented. 621.4060151864
97	Oceanographic Considerations for the Management and Protection of Surfing Breaks Scarfe, Bradley Edward January 2008 (has links) Although the physical characteristics of surfing breaks are well described in the literature, there is little specific research on surfing and coastal management. Such research is required because coastal engineering has had significant impacts to surfing breaks, both positive and negative. Strategic planning and environmental impact assessment methods, a central tenet of integrated coastal zone management (ICZM), are recommended by this thesis to maximise surfing amenities. The research reported here identifies key oceanographic considerations required for ICZM around surfing breaks including: surfing wave parameters; surfing break components; relationship between surfer skill, surfing manoeuvre type and wave parameters; wind effects on waves; currents; geomorphic surfing break categorisation; beach-state and morphology; and offshore wave transformations. Key coastal activities that can have impacts to surfing breaks are identified. Environmental data types to consider during coastal studies around surfing breaks are presented and geographic information systems (GIS) are used to manage and interpret such information. To monitor surfing breaks, a shallow water multibeam echo sounding system was utilised and a RTK GPS water level correction and hydrographic GIS methodology developed. Including surfing in coastal management requires coastal engineering solutions that incorporate surfing. As an example, the efficacy of the artificial surfing reef (ASR) at Mount Maunganui, New Zealand, was evaluated. GIS, multibeam echo soundings, oceanographic measurements, photography, and wave modelling were all applied to monitor sea floor morphology around the reef. Results showed that the beach-state has more cellular circulation since the reef was installed, and a groin effect on the offshore bar was caused by the structure within the monitoring period, trapping sediment updrift and eroding sediment downdrift. No identifiable shoreline salient was observed. Landward of the reef, a scour hole ~3 times the surface area of the reef has formed. The current literature on ASRs has primarily focused on reef shape and its role in creating surfing waves. However, this study suggests that impacts to the offshore bar, beach-state, scour hole and surf zone hydrodynamics should all be included in future surfing reef designs. More real world reef studies, including ongoing monitoring of existing surfing reefs are required to validate theoretical concepts in the published literature. Aramoana Beach Dunedin (New Zealand) ArcGIS ArcSDE artificial surfing reef backscatter Baseline Data Collection bathymetry bathymetric surveying beach morphodynamics beach-state and morphology breaking wave height coastal engineering coastal environment coastal management coastal monitoring coastal processes coastal structures currents economic value EIA environmental data management environmental impact assessment geographic information systems geoid geomorphic surfing break categorisation GIS groin hydrodynamic modelling hydrographic surveying hydrography ICZM incline plane modelling integrated coastal zone management Main Beach Mount Maunganui (New Zealand) Manu Bay Boat Ramp Raglan (New Zealand) measuring water levels morphological coupling multibeam echo soundings oceanography offshore wave transformations Palm Beach Reefs Gold Coast (Australia) RTK GPS salient surf zone hydrodynamics surfing break components surfing reefs surfing tourism surfing wave climate surfing wave parameters Tay Street Mount Maunganui (New Zealand) wave breaking intensity wave climate wave focusing wave modelling wave peel angle wave section length wind effects on waves

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