Thèses sur le sujet « Offshore structures – Hydrodynamics »
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Hodgkinson, Derek Anthony Martin. « Computer graphics applications in offshore hydrodynamics ». Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26705.
Texte intégralApplied Science, Faculty of
Civil Engineering, Department of
Graduate
Schulz, Karl Wayne. « Numerical prediction of the hydrodynamic loads and motions of offshore structures / ». Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
Texte intégralWalker, Daniel Anthony Guy. « Interaction of extreme ocean waves with offshore structures ». Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:6858dc08-1bd4-4195-8893-1af98d5e68e3.
Texte intégral周奮鵬 et Fun-pang Chau. « Numerical methods in wave loading of large offshore structures ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1985. http://hub.hku.hk/bib/B31206797.
Texte intégralAbdolmaleki, Kourosh. « Modelling of wave impact on offshore structures ». University of Western Australia. School of Mechanical Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2008.0055.
Texte intégralCheung, Kwok Fai. « Hydrodynamic interactions between ice masses and large offshore structures ». Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26686.
Texte intégralApplied Science, Faculty of
Civil Engineering, Department of
Graduate
McTaggart, Kevin Andrew. « Hydrodynamics and risk analysis of iceberg impacts with offshore structures ». Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/30733.
Texte intégralApplied Science, Faculty of
Civil Engineering, Department of
Graduate
Lipsett, Arthur William. « Nonlinear response of structures in regular and random waves ». Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25826.
Texte intégralApplied Science, Faculty of
Civil Engineering, Department of
Graduate
Richardson, Mark Damian. « Dynamically installed anchors for floating offshore structures ». University of Western Australia. School of Civil and Resource Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0230.
Texte intégralHildebrandt, Arndt [Verfasser]. « Hydrodynamics of breaking waves on offshore wind turbine structures / Arndt Hildebrandt ». Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2014. http://d-nb.info/1053540329/34.
Texte intégralNwogu, Okey U. « Wave loads and motions of long structures in directional seas ». Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25129.
Texte intégralApplied Science, Faculty of
Civil Engineering, Department of
Graduate
Chau, Fun Pang. « The second order velocity potential for diffraction of waves by fixed offshore structures ». Thesis, University College London (University of London), 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296841.
Texte intégralMuthedath, Premkumar. « Numerical study of nonlinear free-surface flows ». Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-07212009-040300/.
Texte intégralDuong, Chay N. « A study of new-wave theory and an implementation of the new wave theory into GTSELOS computer program ». Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/21492.
Texte intégralTochetto, Luan Grégori 1989. « Estudo experimental de um supressor de vibração PTMD em um modelo reduzido de jumper submerso ». [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264456.
Texte intégralDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências
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Resumo: Tubulações submarinas, tais como risers e jumpers, sofrem carregamentos estáticos e dinâmicos devido a forças ambientais, correntes marítimas e ondas, carregamentos devido aos deslocamentos da unidade flutuante de produção (plataformas ou navios), escoamento interno, além de outras causas. O controle dos deslocamentos oscilatórios dessas tubulações é fundamental para a confiabilidade e vida em fadiga desses sistemas, motivando projetos de pesquisa com tal propósito nos últimos anos. Uma tecnologia em consideração é o Pounding Tuned Mass Damper (PTMD), o qual é o assunto do presente trabalho. Este trabalho apresenta um estudo experimental de um absorvedor de vibrações - o PTMD - acoplado a um modelo de jumper submarino em escala reduzida. O aparato é composto de uma seção de tubo montada em um sistema de suspensão elástica para movimento em duas direções, propiciando similaridade dinâmica parcial entre o protótipo e o modelo. O modelo de PTMD é um sistema massa - mola anexado, similar a um supressor tuned mass damper (TMD), a não ser a adição de um envoltório de batimento, o qual limita o deslocamento da massa do PTMD, dissipando energia do tubo oscilante através do impacto da massa do PTMD contra esse envoltório. Experimentos de oscilação livre e forçada foram realizados na direção vertical, no seco e na água. Os resultados obtidos de amplitude versus frequência foram utilização para determinar a eficácia do absorvedor quando comparado com sua operação a seco. Os resultados deste trabalho são os primeiros passos no desenvolvimento de um dispositivo aplicável a uma real tubulação submarina de petróleo. Os dados adquiridos neste trabalho foram empregados na melhoria e desenvolvimento de um modelo numérico do sistema tubo - PTMD para um simulador computacional
Abstract: Submarine pipelines, such as jumpers and risers, suffer static and dynamic loads due to environmental forces - currents and waves, to the displacements of floating production units (platforms or ships) and to the internal flow, among other causes. Controlling the oscillatory displacements of the pipelines is critical to the reliability and fatigue of these systems, motivating research projects to deal with such issues in the past few years. One technology under consideration is the Pounding Tuned Mass Damper (PTMD), which is the subject of the present work. The current work presents an experimental study of a vibration suppressor - the PTMD - attached to a scaled down submarine jumper model. The apparatus is composed of a test pipe section mounted on an elastic suspension harness for two directions of motion, providing partial dynamic similarity between the prototype and the model. The PTMD model is a lumped mass-spring attachment similar to a tuned mass dumper (TMD) suppressor, but with the addition of a pounding layer, which limits the motion of the PTMD mass, dissipating the energy of the oscillating pipe through the impact of the PTMD mass against that layer. So far, free and forced oscillation experiments were executed, in the vertical direction. The tests were conducted in a water tank, where comparisons of amplitude versus frequency were made to determine the suppressor effectiveness, on air and underwater. The results of this work are the preliminary step on the development of a device applicable to an actual petroleum submarine pipeline. The data gathered from this work was employed in the improvement of a numerical model of the pipe-PTMD system for a computer simulator
Mestrado
Explotação
Mestre em Ciências e Engenharia de Petróleo
Winsor, Fraser N. « Methods for removing inertial force from measured wave impact force signals ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0021/MQ55546.pdf.
Texte intégralZhou, Hongjie. « Numerical study of geotechnical penetration problems for offshore applications ». University of Western Australia. Centre for Offshore Foundation Systems, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0239.
Texte intégralBellezi, Cezar Augusto. « Análise numérica de fenômenos de impacto hidrodinâmico em plataformas offshore ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-23102015-153652/.
Texte intégralThe present work is focused in the study of the violent hydrodynamic impact phenomenon which could jeopardize the offshore platforms operation. In this work three different phenomena involving hydrodynamic impact are studied: green water, wave runup and sloshing. The wave runup consists in the vertical projection of a water column due to wave impact on a transversal structure, such as submersible columns. The green water consists in the water boarding on the deck which could damage the equipment over the oil platform deck. Finally, the sloshing phenomenon is the violent movement of fluid in partially filled tanks, resulting in dangerous impact loads at its walls. The hydrodynamic impact phenomenon has strongly non linear nature and is still a challenge for the naval and offshore engineering its analysis considering all its complexity. The particle methods present advantages in the analysis of phenomena involving fluid structure interaction, large free surface deformation, fragmentation and merging. Therefore, in the present study the Moving Particles Semi-Implicit (MPS) method is used. The MPS is a fully lagrangian method for the simulation of incompressible flows. For the three phenomena studied in the present work a first step of validation is performed. In the validation step the numerical results obtained by the particle method are compared to experimental data presented in the literature. The second step consists in the application of the numerical method to investigate simple mechanisms to mitigate the hydrodynamic impact loads. For example, the effect of the bow shape in the green water phenomenon is studied. Also in this step the use of fixed and floating baffles in order to suppress the sloshing phenomenon are investigated.
Motamed, Dashliborun Amir. « Performance of multiphase packed-bed reactors and scrubbers on offshore floating platforms : hydrodynamics, chemical reaction, CFD modeling and simulation ». Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/30439.
Texte intégralFloating production storage and offloading (FPSO) systems have been introduced to offshore hydrocarbon exploitation sectors as readily movable tools for development of small or remote oil and gas fields in deeper water. These systems are increasingly contemplated for onboard treatment and refining operations of hydrocarbons extracted from undersea reservoirs near extraction sites using embarked packed-bed scrubbers and reactors. Numerous efforts in the literature to uncover the hydrodynamics of multiphase flow in packed beds have disclosed that such reactors continue to challenge us either in their design/scale-up or their operation. Furthermore, when such reactors are subjected to marine conditions, the interaction of phases becomes even more complex, resulting in further challenges for design and scale-up. The proposed research aims at providing important insights into the performance of two-phase flow packed-bed reactors in the context of floating industrial applications. To achieve this aim, a hexapod ship motion simulator with six-degree-of-freedom motions was employed to emulate FPSO movements while capacitance wire mesh sensors (WMS) and electrical capacitance tomography (ECT) coupled with the packed bed scrutinized on-line and locally the two-phase flow dynamic features. The effect of column tilts and oscillations on the hydrodynamic behavior of multiphase packed beds was investigated and then the results were compared with their corresponding onshore analogs. Moreover, potential operational strategies were proposed to diminish fluid maldistribution resulting from bed oscillations as well as for process intensification of heterogeneous catalytic reactions in packed-bed reactors. In parallel with the experiment studies, a 3D transient Eulerian CFD model was developed to simulate the hydrodynamic behavior of multiphase packed beds under column tilts and oscillations. Ultimately, a systematic experimental study was performed to address the amine-based CO2 capture performance of packed-bed scrubbers on board offshore floating vessels/platforms. Apart from gaining a comprehensive knowledge on the influence of translational and rotational movements on multiphase flows in porous media, oil and gas sectors and ship industry would benefit from the results of this work for design and scale-up of industrial reactors and scrubbers.
Unité flottante de production, de stockage et de déchargement
Santos, Marcus Vinicius Franchi dos 1983. « Um estudo comparativo de dutos em vãos livres através de simulações numéricas ». [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265806.
Texte intégralDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências
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Resumo: Vibrações Induzidas por Vórtices em dutos com vãos livres sujeitos a corrente marítima é um problema presente na indústria offshore. Embora significativos esforços tenham sido feitos para entender este complicado problema de interação fluido estrutura, a modelagem numérica para cálculo é ainda um grande desafio. O presente trabalho tem como objetivo principal caracterizar o comportamento dinâmico dos dutos em vãos livres sob os efeitos do fenômeno da vibração induzida por vórtices (VIV). A disponibilidade de diversos programas de cálculo de VIV para estruturas offshore esbeltas facilita a avaliação da vida útil dessas estruturas e reduz o custo de projetos. No entanto, um bom domínio das metodologias adotadas por programas utilizados na indústria e a consciência das limitações correspondentes a diferentes técnicas são fundamentais para que o analista faça uso adequado dessas ferramentas computacionais. Neste sentido, este trabalho faz uma revisão dos diferentes modelos para estimar as forças de VIV devidas à corrente marinha. Para isto, diferentes programas de computador foram utilizados para calcular as vibrações na direção transversal de incidência de corrente, provocadas pelo desprendimento de vórtices em um duto com vão livre. As simulações do comportamento dinâmico da parcela em vão livre do duto foram realizadas utilizando três abordagens, respectivamente: modelos hidrodinâmicos de força de VIV semi-empíricos, no domínio da frequência; modelos hidrodinâmicos de força de VIV semi-empíricos, baseados nos coeficientes de sustentação e número de Strouhal, no domínio do tempo e um modelo hidrodinâmico de wakeoscillator, no domínio do tempo. Os resultados das simulações são analisados através de comparações com dados experimentais. Além disso, as limitações da cada modelo são discutidas
Abstract: Vortex induced vibration (VIV) of free span pipeline subjecting to ocean current is a present problem in the offshore industry. Although significant efforts have done to understand this complicated fluid structure interaction problem, the numerical modeling and predicting is still a big challenge. The primary objective of this work is to characterize the dynamic behavior of pipelines with free span under the effects of the Vortex-Induced Vibration (VIV) phenomenon. Different models to estimate VIV forces due to sea current are discussed. For this purpose, different computer programs were used to predict vibrations in the transverse direction of the current incidence direction, caused by the vortex shedding in a free span of the pipeline. Simulations of the dynamic behavior of a free span portion of the pipeline were carried out by two approaches, respectively: semi-empirical hydrodynamic VIV force model, in frequency domain and, semi-empirical VIV force model based on the lift coefficient and Strouhal number, in time domain and a wake oscillator in time domain. Simulations results are analyzed through comparisons with experimental data and also limitations of the each model are discussed
Mestrado
Explotação
Mestre em Ciências e Engenharia de Petróleo
Morris-Thomas, Michael. « An investigation into wave run-up on vertical surface piercing cylinders in monochromatic waves ». University of Western Australia. School of Oil and Gas Engineering, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0010.
Texte intégralTsukada, Raphael Issamu 1983. « Comportamento dinamico de riser rigido em catenaria devido a vibração induzida por vortices em aguas profundas ». [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265457.
Texte intégralDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica e Instituto de Geociencias
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Resumo: O presente trabalho tem como objetivo principal caracterizar o comportamento dinâmico de risers em configuração catenária (SCR) sob os efeitos do fenômeno da vibração induzida por vórtices (VIV). Estes estudos foram realizados através de experimentos e simulações numéricas. O experimento foi realizado com modelo de SCR em escala reduzida em um tanque de provas sob várias condições simuladas do ambiente, variando a velocidade do carro dinamométrico, a amplitude dos movimentos impostos no topo do modelo, amplitudes e períodos de ondas. As simulações numéricas foram realizadas usando um modelo de VIV criado para a avaliação de risers rígidos verticais. Modificações para o modelo foram implementadas de forma a considerar a inclinação do riser em relação ao escoamento e os movimentos apresentados pela SCR. Os resultados experimentais e numéricos apresentaram algumas características de comportamento semelhantes aos dos risers utilizados para grandes lâminas da água, verificados por outros pesquisadores, tais como: os altos harmônicos da freqüência de desprendimento de vórtices e o comportamento misto de standing e travelling waves. Uma boa concordância foi observada comparação entre os resultados experimentais e numéricos.
Abstract: The primary objective of this work is to characterize the dynamic behavior of steel catenary risers (SCR) under the effects of the Vortex-Induced Vibration (VIV) phenomenon. This study was conducted applying both experimental and numerical approaches. A SCR model test was performed in a towing tank under several simulated environment condition combinations such as; varying the towing speed, riser top forced oscillation amplitudes and surface wave characteristics. Numerical simulations were computed using an empirical VIV model created for the evaluation of top tensioned vertical rigid risers. Modifications to the model were implemented to allow consideration for the inclination of the riser relative to the fluid flow and the movement of the SCR. The experimental e numerical results present some dynamic behavior characteristics similar to that of deep sea risers found by others researcher mainly high harmonics of the vortex shedding frequency and a mix of standing and traveling wave behavior. Results from the comparison of experimental and numerical results have shown a good agreement.
Mestrado
Explotação
Mestre em Ciências e Engenharia de Petróleo
Kitney, Neil. « Hydrodynamic loading of catenary mooring lines ». Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342219.
Texte intégralMurray, Brian A. « Hydrodynamic loading due to appurtenances on jacket structures ». Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239242.
Texte intégralTheophanatos, Andreas. « Marine growth and the hydrodynamic loading of offshore structures ». Thesis, University of Strathclyde, 1988. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=26411.
Texte intégralSarkar, Abhijit. « Dynamics of moored offshore structures in random seas ». Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284464.
Texte intégralCarstens, Baerbel. « Hydrodynamic forces on cylinders subjected to single and multiple frequency excitation ». Thesis, University of Strathclyde, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366670.
Texte intégralIndiyono, Paulus. « Hydrodynamic loading due to appurtenances on offshore structural members ». Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307828.
Texte intégralZhou, Chao Ying. « Effects of combination motions on cylinders in waves and currents ». Thesis, Imperial College London, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339445.
Texte intégralNaghipour, Morteza. « The accuracy of hydrodynamic force prediction for offshore structures and Morison's equation ». Thesis, Heriot-Watt University, 1996. http://hdl.handle.net/10399/738.
Texte intégralCaputo, Piermodesto. « Hydrodynamic loading and structural dynamic assessment of offshore concrete lighthouse ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Trouver le texte intégralLeroy, Vincent. « Aérodynamique instationnaire pour l'analyse de la tenue à la mer des éoliennes flottantes ». Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0050/document.
Texte intégralAccurate numerical simulation of thesea keeping of Floating Wind turbines (FWTs) is essential for the development of Marine Renewable Energy. State-of-the-art simulation tools assume a steady flow on the rotor. The accuracy of such models has been proven for bottom-fixed turbines, but has not been demonstrated yet for FWTs with substantial platform motions. This PhD thesis focuses on the impact of unsteady aerodynamics on the seakeeping of FWTs. This study is done by comparing quasi-steady to fully unsteady models with a coupled hydro-aerodynamic simulation tool. It shows that unsteady load shave a substantial effect on the platform motion when the rotor is highly loaded. The choice of a numerical model for example induces differences in tower base bending moments. The study also shows that state of the art quasi-steady aerodynamic models can show rather good accuracy when studying the global motion of the FWTs. Vertical Axis Wind Turbines (VAWTs) could lower infrastructure costs and are hence studied today for offshore wind projects. Unsteady aerodynamics for floating VAWT sand its effects on the sea keeping modelling have been studied during the PhD thesis,leading to similar conclusions than for traditional floating Horizontal Axis Wind Turbines (HAWTs). Those turbines have been compared to HAWTs. The study concludes that, without blade pitch control strategy, VAWTs suffer from very high wind thrust at over-rated wind speeds, leading to excessive displacements and loads. More developments are hence needed to improve the performance of such floating systems
Kernot, Matthew Peter. « The second-order forcing and response of offshore structures in irregular seas ». Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306887.
Texte intégralKim, Yonghwan 1964. « Computation of higher-order hydrodynamic forces on ships and offshore structures in waves ». Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/79979.
Texte intégralErcolanelli, Julien. « Étude numérique et expérimentale d'un système couplé stabilisateur et récupérateur d'énergie des vagues Experimental and numerical investigation of sloshing in anti-roll tank using effective gravity angle Experimental and numerical assessment of the performance of a new type passive anti-roll stabilisation system ». Thesis, Brest, École nationale supérieure de techniques avancées Bretagne, 2019. http://www.theses.fr/2019ENTA0008.
Texte intégralGeps Techno's development is based on an innovative concept of a floating structure intended to produce electrical energy from several renewable marine energy sources, including wave power. The wave power system developed by Geps Techno is based on circulating water and creating a vortex within it. By taking advantage of the liquid hull phenomenon, the concept can also be used as a stabilization system for a ship or any other floating platform. The short-term objective of the company is the development of this technology allowing the stabilization and recovery of wave energy and for which there remain technological obstacles to be removed in order to achieve the viability and profitability of the system. To do this, in October 2015 Geps Techno launched the IHES (Integrated Harvesting Energy System) project, which consists of building a demonstrator of its wave power platform concept. The IHES project is one of the projects of the roadmap of the "Ecological ships" plan of New Industrial France. It is supported by Bpifrance within the framework of the Investments for the Future - Industrial Projects for the Future program. In order to master the objectives of stabilization and energy recovery, Geps Techno is studying the technological aspects necessary to switch from the energy available at wave level to that available at the wave turbine turbine. The Ph.D. thesis work supported by Fourestier in May 2017 focused on a first part "Definition and control of internal flows in the wave power system". Using CFD modeling, the latter resulted in operational models characterizing internal flows. This Cifre Ph.D. thesis follows on from Fourestier's work and deals with a second part "Modeling of the coupled platform / wave power system". All of this work should lead to an operational computer code correlated with experimental results making it possible to study the internal flow and the behavior of the float subjected to swell
Zhang, Jian. « Hydrodynamic behavior of packed-bed reactors on a floating platform : liquid distribution and drainage dynamics ». Doctoral thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/68634.
Texte intégralTo fill the gap between increasing energy demand and depletion of onshore hydrocarbon production, offshore hydrocarbon exploitation is increasingly contemplated especially the gas/oil fields in the deeper water. Meantime, large amount of deployed processing units for hydrocarbon productions must comply with the environmental codes designated for maritime protection. Systems such as embarked packed-bed reactors and scrubbers inevitably become one of the most promising options to achieve both purposes. Numerous efforts in literature to unveil the hydrodynamics of multiphase flow in packed beds reveal that challenges persist either in their design/scale-up or during the operations. Moreover, exposing these reactors to harsh marine conditions such as the convolution of ship dynamics and hydrodynamics inside packed-bed reactors leads to even more complex situations to maintain the proper operation performance of packed-bed reactors under floating conditions. A lot of evidence from literature has pointed out the failure of random and structured packings and open-cell foams, to prevent liquid maldistribution in packed beds destined to operate on-board sailing ships and floating platforms. Research efforts must therefore continue in the quest for robust internals capable of resilience against liquid maldistribution in gas-liquid reactors/separation units. The proposed Ph.D. research aims at firstly following a sound path to adapt commercially existing internals being capable of preserving performance similar to landbased packed beds. To the best of literature exploring, the sensitivity and susceptibility of monolith reactors to maldistribution subjected to offshore conditions have yet to be investigated. Rather than focusing on a study of monolith beds alone, Chapter 1 opts for a broader experimental campaign including a random packing and an open-cell foam packing for the sake of systematic comparisons of the liquid distribution under floating conditions. Liquid distribution of embarked columns packed with various internals under wide gas/liquid flow range is systematically compared with the assistance of wire mesh sensor (WMS) and six-degree-of-freedom emulator hexapod. Severe offshore weather conditions threaten the operation safety of floating packed beds especially encountering extreme situations such as cyclone, iceberg episodes and so forth. To ensure the safety of staff and facilities, the onboard packed columns must be immediately shutdown to avoid critical safety concerns under such circumstances. Therefore, knowledgebase of liquid draining dynamics in floating packed beds is the essence to ensure timely discharge of liquid. Nevertheless, the study regarding liquid drainage dynamics of packed beds under floating conditions is scarce to say the least. Then, Chapter 2 compares liquid draining of packed columns embarking on floating platforms with static land-based one experimentally. Other than that, the influence of ship motions (e.g., roll, roll & pitch, heave etc.) with different oscillation amplitudes and periods on liquid draining dynamics is investigated to deepen the insights. vi In parallel with the experimental study, a 3D transient Euler-Euler CFD model is employed as a supplementary analysis to further deepen the understanding of liquid drainage dynamics in floating packed beds. More factors possibly affecting the draining dynamics are exploited by numerical simulation. Consequently, Chapter 3 highlights the comprehensive influence of liquid properties, bed structure and moving types instead of focusing on impact of movements alone. Meanwhile, with sufficient body of experimental campaign, the validity and accuracy of model are strongly endorsed.
Liou, Sy Yeuan. « Hybrid boundary integral equation method for the hydrodynamic analysis of marine structures in open and confined water ». Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315619.
Texte intégralNajafian, G. « Local hydrodynamic force coefficients from field data and probabilistic analysis of offshore structures exposed to random wave loading ». Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317214.
Texte intégralAllsop, Steven Christopher. « Hydrodynamic modelling for structural analysis of tidal stream turbine blades ». Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/33219.
Texte intégralCathelain, Marie. « Développement d’un modèle de simulation déterministe pour l’étude du couplage entre un écoulement atmosphérique et un état de mer ». Thesis, Ecole centrale de Nantes, 2017. http://www.theses.fr/2017ECDN0001/document.
Texte intégralModelling the dynamic coupling of ocean-atmosphere systems requires a fundamental and quantitative understanding of the mechanisms governing the windwave interactions: despite numerous studies, our current understanding remains quite incomplete and, in certain conditions, sparse field observations contradict the usual theoretical and stochastic models. Within the context of a growing exploitation of the offshore wind energy and the development of met ocean models, a fine description of this resource is a key issue. Field experiments and numerical modelling have revealed that atmospheric stability and wave effects, including the dynamic sea surface roughness, are two major factors affecting the wind field over oceans. A numerical tool has been implemented in order to study the coupling between an atmospheric flow and the seastate. A massively parallel large-eddy simulation developed by P. Sullivan at the National Center for Atmospheric Research is then coupled to a High-Order Spectral wave model developed at the Hydrodynamics,Energetics & Atmospheric Environment Laboratory in Ecole Centrale de Nantes. Numerous configurations of wind and sea states are investigated. It appears that, under strongly forced wind conditions above a small sea state, the semi-empirical laws referred to as standards in the international guidelines are a good approximation for the vertical profile of the mean wind speed. However, for light winds overlying fast-moving swell, the presence of a wave induced wind jet is observed, invalidating the use of such logarithmic laws
Scarfe, Bradley Edward. « Oceanographic Considerations for the Management and Protection of Surfing Breaks ». The University of Waikato, 2008. http://hdl.handle.net/10289/2668.
Texte intégralNarayanan, Suchithra. « Experimental analysis of a nonlinear moored structure ». Thesis, 1999. http://hdl.handle.net/1957/33527.
Texte intégralKing, Paul E. « Deterministic and stochastic control of nonlinear oscillations in ocean structural systems ». Thesis, 2006. http://hdl.handle.net/1957/29586.
Texte intégralGraduation date: 2006
Agarwal, Puneet 1977. « Structural reliability of offshore wind turbines ». 2008. http://hdl.handle.net/2152/17723.
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Gottlieb, Oded. « Nonlinear oscillations, bifurcations and chaos in ocean mooring systems ». Thesis, 1991. http://hdl.handle.net/1957/36341.
Texte intégralGraduation date: 1992
Rodriguez, Marijuan Alberto. « Offshore Floating Platforms : Analysis of a solution for motion mitigation ». Thesis, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215507.
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