With growing awareness of climate change and an increased interest in renewable energy, resources like offshore wind are projected to grow in the near future. One key issue within offshore wind is how to stabilize the floating system when it experiences large wind and wave forces that impact its performance and shorten its operating life. Researchers have been exploring structural control methods and creating modeling tools to evaluate the performance of the control methods. One such tool is OpenFAST, the industry standard for modeling wind turbine dynamics, and the goal of this paper is to build upon the existing capabilities of OpenFAST. Inerter-based structural control methods offer arguably better performance than traditional vibration absorbers, and the configuration proposed in this paper also offers the ability to use a generator as an element in the structural controller. This allows extra energy to be generated along with the improvement in vibration absorption. Through this study, this inerter-based control method is explored through the lens of an established modeling tool to provide the validation for the model to explore which load cases the inerter performs best in and what design considerations must be made. In addition, the energy harvesting potential of the inerter system is evaluated and shown to increase the system's capabilities especially under stormy ocean conditions. / Master of Science / With growing awareness of climate change and an increased interest in renewable energy, resources like offshore wind are projected to grow in the near future. One key issue within offshore wind is how to stabilize the floating system when it experiences large wind and wave forces which impact its performance and shorten its lifespan. Researchers have been exploring several methods and creating modeling tools to evaluate the performance of control methods. One such tool is OpenFAST, the industry standard for modeling wind turbine dynamics, and the goal of this paper is to build upon the existing capabilities of OpenFAST. Structural control methods based on an element called an inerter offer arguably better performance than traditional vibration absorbers. The design in this paper also offers the ability to use an electrical generator as an element in the structural controller. This allows extra energy to be generated along with the reduced vibrations. Through this study, this inerter-based control method is explored through the lens of an established modeling tool to provide validation for the model. Another goal is to explore which scenarios the inerter performs best and what design considerations must be made for future development. In addition, the energy harvesting potential of the inerter system is evaluated and shown to increase the system's capabilities.

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Detta produktutvecklingsarbete har utförts i samarbete med företaget, Pegil Innovations AB. Syftet med projektet var att utveckla en hanteringslösning för processat avloppsslam (damm) på boendeplattformar i offshore industrin. Processen för projektet kombinerade Front-End processen med detaljer från Set-Based Concurrent Engineering. Projektet inleddes med en förstudie och användarstudier för att få djupare kunskap inom ämnet. Detaljer som var viktigt för projektet samlades i en kravspecifikation som användes som stöd genom hela processen. Därefter följde en idégenerering för att utforska lösningar. Från denna framkom fem idélösningar som utforskades vidare genom en fördjupning och jämförelse mot en ny kravspecifikation. Denna var en uppdaterad version av den första för att bättre reflektera vilka krav och önskemål som kunde ställas på idélösningarna. När idélösningarna hade utforskats utfördes en ny idégenerering som ledde till att idélösningarna utvecklades till två koncept. Det fördjupades kring koncepten och dessa jämfördes mot kravspecifikationen. Sedan följde ytterligare en idégenerering för att undersöka hur koncepten kunde förbättras. Slutligen utfördes ett konceptval. Resultatet blev en påse, som fästs runt en stos, som fylldes med damm och sedan sögs luften ur (för att bilda ett undertryck) samt att påsen värmeförseglades. Personalen kan sedan enkelt bära iväg påsen för att kassera denna tillsammans med dammet. / This product development project has been carried out in cooperation with the company, Pegil Innovations AB. The purpose of the project was to develop a management solution for processed sewage sludge (dust) on accommodation vessels in the offshore industry. The process of the project combined the Front-End process with details from Set-Based Concurrent Engineering. The project started with a preliminary study and user studies to obtain deeper understanding regarding the relevant knowledge area. Details that were of importance to the project was gathered in a specification that was used through the entire process as a support. Then an idea generation was preformed, to discover and explore different solutions. From the idea generation five different idea solutions were created. These five solutions were explored deeper and then compared to a new specification. The specification was an updated version from the first one to better reflect what conditions the idea solutions should meet. When the idea solutions were explored, a new idea generation was performed, resulting in two concepts. These concepts were explored deeper and then compared to a new specification. Then followed another idea generation to explore how the concepts could be improved. In conclusion to the project a concept was chosen. The result was a plastic bag which was fastened around a spigot, that was filled with the dust and then the air was withdrawn (to create a vacuum). Then the opening of the plastic bag was heat sealed. The personal could then easily carry the bag to discard this together with the dust.

<p>Outsourcing has grown more so than any other sector of IT services. According to a research by the analytic company Gartner soon four of ten jobs in the IT sector will be outsourced. For a nation like Sweden that means about 40,000 jobs going abroad. Business managers look to outsourcing as a means of reducing their operating cost and their need for capital spending. Companies turn to outsourcing to save money and seek expertise outside. As the competition is tough these days especially for small-to-medium sized enterprises, paying someone else to do work inexpensively is one way to get around.</p><p>Small-to-medium sized enterprises (SMEs) have become a sector buried in all the media "hype". This essay is written in an effort to help SMEs uncover the relevant strategic offshoring issues. Many managers fail to figure out India after their first visit, other get confused by the culture differences. The purpose of this essay is to map out the different ways to outsource to India and to assist managers with all necessary information that is needed. Which ownership models there are and how to choose the one that fits you. How the different ways and methods lack and what is their limitation. Not to mention how to avoid hindrance during the process. The essay will also map the Indian outsourcing industry, the major industry players and the major outsourcing locations.</p> / <p>Outsourcing är ett av de störst växande områdena i dagens IT-industri. Enligt analysföretaget Gartner kommer så småningom vart fjärde IT-jobb i den industrialiserade delen av världen att ha flyttat till låglöneländer som Indien. I siffror handlar det om 40 000 jobb bara i Sverige. IT-företagen söker efter billigare, snabbare, flexiblare och modernare lösningar. Samtidigt som man förväntar sig att kvalitén är bibehållen.</p><p>IT-sektorn för små och medelstora företag är konkurrens kraftigare än någonsin. Att använda sig av utomstående expertis i form av offshore outsourcing är ett gensvar. De större företagen är dem som nämns i tidningar när det pratas om outsourcing, små och medelstora företag har hamnat i skymundan i samband med outsourcing av IT-verksamhet. Denna uppsats är skriven för att belysa de mindre företagen om de unika möjligheter offshore outsourcing till Indien erbjuder. Många företagsledare misslyckas att komma underfund med Indien efter första besöket, andra blir förvirrade i form av kulturkrockar. Syftet med denna kandidat uppsats är att kartlägga de olika sätten att outsourca till Indien och bistå företagsledare med information om hur processer inom fenomenet outsourcing går till. Vilka ägarskapsmodeller det finns att välja ibland samt visa vilka eventuella brister och/eller begränsningar metoderna har. Samt hur man hanterar risker. Uppsatsen kommer även att ge en inblick på den Indiska outsourcing industrin, de stora nyckel företagen och perspektiv utifrån geografiskt läge.</p>

Suction caissons are a new foundation option for offshore wind turbines. This thesis is focussed on the behaviour of suction caisson foundations in sand and in clay during installation, and under subsequent vertical and combined moment-lateral loadings. The research is based on extensive experimental work carried out using model scaled caissons. The analysis of the results allowed the determination of parameters for hyperplasticity models. Model caissons were vertically loaded in loose and dense sands to study in service states and plastic behaviour. Bearing capacity increased with the length of the caisson skirt. The bearing capacity formulation showed that the angle of friction mobilised was close to the critical state value for loose sands and close to those of peak values due to dilation for dense sands. The vertical load increased, though at a lower rate than during initial penetration, after large plastic displacements occurred. A hardening law formulation including this observed behaviour is suggested. In sand the installation of caissons by suction showed a drastic reduction in the net vertical load required to penetrate the caisson into the ground compared with that required to install caissons by pushing. This occurred due to the hydraulic gradients created by the suction. The theoretical formulations of the yield surface and flow rule were calibrated from the results of moment loading tests under low constant vertical loads. The fact that caissons exhibit moment capacity under tension loads was considered in the yield surface formulation. Results from symmetric and non symmetric cyclic moment loading tests showed that Masing’s rules were obeyed. Fully drained conditions, partially drained and undrained conditions were studied. Caisson rotation velocities scaled in the laboratory to represent those in the field induced undrained response for relevant periods of wave loading, a wide range of seabed permeabilities and prototype caisson dimensions. Under undrained conditions and low constant vertical loads the moment capacity of suction caissons was very small. Under partially drained conditions the moment capacity decreased with the increase of excess pore pressure. In clay, vertical cyclic loading around a mean vertical load of zero showed that in the short term the negative excess pore pressures generated during suction installation reduced vertical displacements. The yield surface and the flow rule were determined from moment swipe and constant vertical load tests. The moment capacity was found to depend on the ratio between the preload Vo and the ultimate bearing capacity Vu. Gapping response was observed during cyclic moment loading tests, but starting at smaller normalised rotations than in the field. The hysteresis loop shape obtained during gapping cannot be reproduced by means of the Masing’s rules.

In addition to vertical loads, the foundations of offshore structures are subjected to horizontal loads and overturning moments as a result of environmental (wind and wave) loading. The behaviour of circular footings on cohesive soil under conditions of combined vertical, horizontal and moment (V, H, M) loading is the primary concern of this thesis. A programme of physical model tests, involving combined loading of circular footings on reconstituted Speswhite kaolin, is reported. The shape of footing used is typical of the "spudcan" foundations of independent leg jack-up drilling platforms. Previous experience with combined loading of footings on sand has revealed that the observed load:displacement behaviour is best understood, and theoretically modelled, in terms of work hardening plasticity theory. The present tests on clay confirm this, and the results are interpreted to give empirical expressions for (i) the combined load yield surface in V:H:M space, and (ii) a suitable flow rule to allow prediction of the corresponding footing displacements (z, h, &theta;) during yielding. Extension to a complete plasticity model is achieved using theoretical stiffness factors to define elastic behaviour, and theoretical lower bound bearing capacity factors (derived specifically for this work) to define the size of the yield surface as a function of vertical penetration. The predictive capabilities of the numerical model are evaluated by retrospective simulation of various footing tests. Finally some plane frame structural analyses of a representative jack-up unit are described; some of these analyses incorporate the plasticity-based numerical model of spudcan footing behaviour under combined loads.

Wind power is a rapidly growing industry worldwide, both on- andoffshore. Most of the good locations onshore in continental Europeare in use today, which has prompted a move offshore in recentyears. Europe has by far the most offshore wind turbinesinstalled, mostly located in the North sea.The low hanging fruits are locations with relatively shallowwaters (up to 45-50 meters), a high and steady wind speed and isclose to grid connections onshore. Big parts of the North Sea aresuitable for this, but many places with good wind conditionsworldwide are too deep. The next step for the industry is to moveto these deeper waters, with the help of floating wind turbines.The first prototype floating turbines have been running for acouple of years, with even larger, albeit still pretty small, windfarms in the planning stage.This thesis looks on the possibility of building large floatingwind farms in the future, specifically in the eastern most part ofthe North Sea - Skagerrak. Several different factors andstakeholders have been mapped out and important factors such aswater depth, wind speed and seabed conditions considered to createfour different future scenarios. Each scenario has been evaluatedtechnically and Levelized Cost of Energy (LCOE) has beencalculated to be able to compare the different locations.Since the technology is very new and under development, theinitial costs are high. This gives the lower LCOE of 149 €/MWh.Many new developments are however expected in the years to come,which would lower the investment cost considerably, by up to 40%according to some sources. This would lower the LCOE to under 100€/MWh.It is however also found that these investments carry many otherpositive effects, such as developing a new carbon neutraltechnology in Scandinavia which could become a big exportworldwide. The social acceptance of bottom fixed foundationoffshore (close to shore) and onshore wind power is also falling,and this would also be a big plus for floating offshore wind as itcan be built so far offshore it can't be seen from land. BothSweden and Denmark have big power plants closing in the comingdecades, nuclear power in Sweden and coal fired power plants inDenmark. These need to be replaced either by import or by newcarbon neutral power production.

Utilizados na extração de petróleo em alto mar, os risers são elementos que conectam a unidade flutuante ao poço no fundo do mar. Eles estão sujeitos às condições ambientais do local onde estão instalados, as quais podem variar no tempo. Em geral, divide-se o estudo do comportamento global dos risers em duas análises: estática e dinâmica. Na análise estática são levados em conta os carregamentos que podem ser considerados constantes no tempo, são eles: peso próprio, empuxo e força da correnteza. Já na análise dinâmica são considerados os carregamentos causados pela movimentação da unidade flutuante, pelas ondas e pela liberação de vórtices. A dinâmica de risers é essencialmente não-linear, principalmente por causa do amortecimento viscoso, que é quadrático com a velocidade relativa, e devido ao contato unilateral entre o riser e o solo. O problema dinâmico pode ser simulado de duas maneiras: no domínio do tempo e no domínio da freqüência. A análise do domínio do tempo é, geralmente, mais demorada, pois a solução é obtida para cada passo de tempo, porém as não-linearidades inerentes ao comportamento da estrutura podem ser consideradas de forma direta. A análise no domínio da freqüência, por sua vez, costuma ser mais rápida, pois o estado estacionário é diretamente obtido, porém, as não-linearidades do problema devem ser devidamente tratadas. O objetivo deste trabalho foi estudar a dinâmica global de risers com foco na modelagem das não-linearidades no domínio do tempo, bem como estudar uma forma de lineariza-las para o domínio da freqüência. Partiu-se de uma análise estática pré-existente, que no domínio da freqüência é a configuração em torno da qual o riser se movimenta. O modelo dinâmico foi obtido através do Método dos Elementos Finitos e o riser foi representado por um elemento de pórtico. Para a análise no domínio da freqüência uma forma de linearização do amortecimento viscoso foi desenvolvida neste trabalho baseada, em uma metodologia já utilizada em casos bidimensionais. Além disso, o contato com o solo foi representado por molas lineares, que recuperam o movimento no plano horizontal e a curvatura corrigida através de uma técnica de camada limite. Com base nos resultados obtidos, pode-se dizer que essas linearizações tiveram o efeito desejado, pois compararam muito bem com os resultados do modelo não-linear. Já no domínio do tempo o amortecimento viscoso pode ser representado de forma não linear, assim como o contato com solo, representado através do contato unilateral, atrito, força de sucção e trincheira. Foram feitas comparações, sempre que possível, com o software comercial Orcaflex 9.2a. / Used in offshore oil exploitation risers are elements that connect the floating unit to the oil well on the seabed. They are exposed to the environmental conditions of the site where they are installed. Normally, the risers global behavior is divided in static and dynamic analyses. The static loads acting on the pipe are: weight, buoyancy and current load. The loads considered in the dynamic analysis are caused by the floating units motion and by the waves. The riser dynamics is essentially non-linear mainly due to the viscous damping, which is quadratic in velocity and due to the unilateral contact between the riser and the seabed. The dynamic simulation can be performed in time domain and in frequency domain. The time domain analysis usually takes longer to perform because the solution is obtained at each time-step. However, the non-linearities of the problem can be considered. The frequency domain analysis is normally faster than the time domain analysis, once the stationary state is directly obtained, nevertheless, the non-linearities must be removed. The objective of this work is to study the risers global dynamics focusing on the modeling of the non-linearities in time domain, as well as removing them for the frequency domain analysis. The static configuration is the initial configuration of the dynamic analysis and the frequency domain dynamic is modeled to be a perturbation of it. The dynamic model was obtained through the Finite Element Method and the riser was represented by a beam element. The only non-linearities covered in this work are caused by the viscous damping and the soil-structure contact. For the frequency domain analysis it was developed, in this work, a way to linearize the viscous damping based on a methodology already in use for two-dimensional analysis. Besides that, the contact with the seabed was represented by linear springs and the curvature was corrected afterwards through a boundary layer technique. Considering that the results compared very well with the ones obtained with a non linear model, one can say that these linearizations had the desired effect. In the time domain analysis the viscous damping could be represented in the non linear form as well as the soil-structure contact, which was represented through the unilateral contact, friction, suction force and trench. Whenever possible, the results were compared with the ones obtained with Orcaflex 9.2a.

O presente trabalho é focado no estudo dos violentos fenômenos de impacto hidrodinâmico que podem prejudicar a operação de plataformas offshore. São três os fenômenos abordados neste trabalho: o green water, o wave runup e o sloshing. O fenômeno de wave runup consiste na projeção vertical de uma coluna de água devido ao impacto de ondas em estruturas transversais. O fenômeno de green water consiste no embarque de água no convés, podendo danificar os equipamentos da planta de produção. Por fim, o sloshing consiste no movimento violento de fluído em tanques parcialmente preenchidos, resultando em perigosos carregamentos em suas paredes. Tais fenômenos possuem natureza altamente não linear e sua análise, considerando-se toda a sua complexidade, ainda constitui um desafio para a engenharia naval e oceânica. Os métodos de partículas têm se destacado no tratamento de tais fenômenos envolvendo interação fluído-estruturas, grandes deformações e fragmentação de superfície livre. Desta maneira, optou-se pelo emprego do método de partículas Moving Particles Semi-Implicit (MPS) neste trabalho para o estudo dos fenômenos de impacto hidrodinâmico. O MPS é um método totalmente lagrangeano para escoamentos incompressíveis. Para os três fenômenos abordados neste trabalho há uma primeira etapa de validação, na qual os resultados numéricos são comparados a resultados experimentais da literatura. Uma segunda etapa é baseada na aplicação do método numérico na análise de ferramentas para a mitigação dos esforços resultantes do impacto hidrodinâmico. Nesta etapa é investigada a influência do formato da proa no fenômeno de green water e a utilização de anteparas fixas e flutuantes para a mitigação de sloshing em tanques. / The 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.

A energia eólica é uma das fontes de energia renovável mais promissoras e que cresce mais rapidamente em todo o mundo. O uso da energia eólica pode contribuir para reduzir as emissões de gases de efeito estufa derivados da queima de combustíveis fósseis. Estima-se que o Brasil dispõe de um significativo potencial eólico offshore na sua Zona Econômica Exclusiva de cerca de 1,78 TW. Entretanto, um dos fatores limitantes para o desenvolvimento da energia eólica offshore no Brasil é a inexistência de um marco regulatório. O marco regulatório é uma condição essencial para atrair investimentos no setor e permitir o desenvolvimento do potencial latente. Este estudo tem como objetivo analisar princípios e experiências regulatórias brasileiras e internacionais para subsidiar o debate na formulação de instrumentos normativos com vista a inserção da energia eólica offshore no Brasil. O estudo apresenta um panorama do estado da arte e das tendências tecnológicas para geração de energia eólica offshore que ajuda a compreender como a construção e operação de usinas pode provocar impactos socioambientais e conflitos no espaço oceânico. Uma síntese do conceito de potencial eólico é elaborada, e as rendas econômicas do recurso eólico offshore são analisadas ressaltando-se a necessidade de atuação do Estado na arbitragem de sua extração e distribuição. Por meio da investigação do arcabouço jurídico-regulatório brasileiro, e com uso da metodologia descritiva, constatou-se que não há instrumentos capazes de dar suporte ao desenvolvimento de parques eólicos offshore no Brasil. A partir da análise de princípios e experiências regulatórias brasileiras em geração de energia eólica onshore, geração de energia hidrelétrica, exploração e produção de petróleo e gás natural, e, em geração de energia eólica offshore do Reino Unido, Alemanha, Dinamarca, Holanda, Bélgica, China e Estados Unidos, foram elaborados quadros de referências para servirem de base para o caso do Brasil. Em conclusão, princípios dos modelos brasileiros para outorga de usinas hidrelétricas; princípios do modelo de exploração e produção de petróleo e gás natural, assim como das experiências internacionais em energia eólica offshore aderentes ao ambiente institucional do Brasil, podem ser adotados na formulação de instrumentos jurídicos e normativos com vista a inserção da energia eólica offshore no país. / Wind power is one of the most promising and fastest growing renewable energy sources in the world. The use of wind power can contribute to reduce greenhouse gas emissions from burning fossil fuels. It is estimated that Brazil has a significant offshore wind potential in its Exclusive Economic Zone of about 1.78 TW. However, one of the limiting factors for the development of offshore wind power in Brazil is the lack of a regulatory framework. The regulatory framework is an essential condition to attract investments in the sector and allowing the development of latent potential. This study aims to analyze Brazilian and international regulatory principles and experiences to support the debate in the formulation of normative instruments for the insertion of offshore wind energy in Brazil. The study presents an overview of the state of the art and technological trends for offshore wind power generation that helps to understand how the construction and operation of power plants can cause socio-environmental impacts and conflicts in the ocean space. A synthesis of the concept of wind potential is elaborated, and the economic rents of the offshore wind resource are analyzed emphasizing the necessity of State action in the arbitration of its extraction and distribution. Based on the investigation of the Brazilian legal-regulatory framework and by using the descriptive methodology it was verified that there are no instruments capable of supporting the development of offshore wind farms in Brazil. Based on the analysis of Brazilian principles and regulatory experiences in onshore wind power generation, hydroelectric power generation, oil and natural gas exploration and production, and in offshore wind power generation in the United Kingdom, Germany, Denmark, the Netherlands, Belgium, China, and United States, frameworks of the conceptual references were developed to serve as a basis for the case of Brazil. In conclusion, principles of the Brazilian model for the grant of hydroelectric plants; principles of the Brazilian model for oil, and natural gas exploration and production, as well as of the international offshore wind experiences adhering to the institutional environment of Brazil, can be adopted in the formulation of legal and normative instruments aiming the insertion of offshore wind power in the country.