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This thesis investigates wave loading on bodies in the free surface using smoothed particle hydrodynamics (SPH). This includes wave loading on fixed bodies, waves generated by heaving bodies in still water and the heave response of a body in waves, representing a wave energy device. SPH is a flexible Lagrangian technique for CFD simulations, which in principle applies to steep and breaking waves without special treatment allowing us to simulate highly nonlinear and potentially violent flows encountered in a real sea. However few detailed tests have been undertaken even with small amplitude waves.This research uses the open-source SPH code SPHysics. First two forms of SPH formulation, standard SPH with artificial viscosity and SPH-Arbitrary Lagrange Euler (ALE) with a Riemann solver, are used to simulate progressive waves in a 2-D tank. The SPH-ALE formulation with a symplectic time integration scheme and cubic spline kernel is found to model progressive waves with negligible dissipation whereas with the standard SPH formulation waves decay markedly along the tank. We then consider two well-defined test cases in two dimensions: progressive waves interacting with a fixed cylinder and waves generated by a heaving semi-immersed cylinder. To reduce computer time in a simple manner a variable particle mass distribution is tested with fine resolution near the body and coarse resolution further away, while maintaining a uniform kernel size. A mass ratio of 1:4 proved effective but increasing to 1:16 caused particle clumping and instability. For wave loading on a half-submerged cylinder the agreement with the experimental data of Dixon et al. (1979) for the root mean square force is within 2%. For more submerged cases, the results show some discrepancy, but this was also found with other modelling approaches. For the heaving cylinder, SPH results for the far field wave amplitude and vertical force on the cylinder show good agreement with the data of Yu and Ursell (1961). The variable mass distribution leads to a computer run time speedup of nearly 200% in these cases on a single CPU. The results of the vertical force and wave amplitude are shown to be quite sensitive to the value of the slope limiter in the Riemann solver for the 2-D heaving cylinder problem. A heaving 2-D wedge or 3-D cone whose oscillatory vertical motion is prescribed as the elevation of a focused wave group is a precise test case for numerical free-surface schemes. We consider two forms of repulsive boundary condition (Monaghan & Kos, 1999, and Rogers et al., 2008) and particle boundary force (Kajtar and Monaghan, 2009) for the 2-D wedge case, comparing the result with the experimental data of Drake et al. (2009). The repulsive boundary condition was more effective than the particle boundary force method. Variable particle mass with different kernel sizes was then tested for 2-D problems for mass ratios of 1:4, 1:16 and 1:4:16 with satisfactory results without particle clumping and instability. For the 3-D cone case, SPH reproduces the experimental results very closely for the lower frequency tested where there is no separation from the bottom surface of the body but for the higher frequencies the magnitudes of force minima were underestimated. The mass ratios of 1:8 and 1:8:27 in two and three nested regions are tested for the 3-D cone problem where a computer run time speedup of nearly 500% is achieved on 16 processors for the mass ratio of 1:8.Finally, the floating body of a heaving wave energy device known as the Manchester Bobber is modelled in extreme waves without power take-off. The results for a single float are in approximate agreement with the experiment.

O uso contínuo de combustíveis fósseis já se mostrou deletério há anos, além de ser um meio energético finito. Por este motivo, a demanda atual e futura por sistemas de energia limpa é grande. Muito embora já existam diversas estruturas dedicadas a extrair energia do mar, o conceito em que se pretende trabalhar é inovador e de tecnologia nacional. Este tema foi desenvolvido inicialmente em uma abordagem teórica pelo então aluno de engenharia naval Daniel Prata Vieira e sua colega Ana Luísa Orsolini, como Trabalho Final do curso de Engenharia Naval e Oceânica da Escola Politécnica da USP, orientados pelo Prof. Dr. André Luis Condino Fujarra. Vieira & Orsolini (2011) [1] abordaram de uma forma diferente o tema de geração de energia por ondas do mar, trazendo à tona o uso da já consagrada plataforma monocoluna - protótipo que rendeu diversos prêmios de inventor do ano da Petrobrás, além de patente, ao Tanque de Provas Numérico, laboratório do departamento de engenharia naval da POLI-USP. O trabalho dos alunos Daniel e Ana também foi reconhecido nacionalmente recebendo o Prêmio Petrobras de Tecnologia 2011 no tema de Tecnologia de Energia. A continuação do trabalho consiste em levar a fundo alguns pontos importantes relacionados ao dimensionamento da plataforma para otimizar a geração de energia através do movimento relativo entre ela e um corpo flutuante interno ao seu moonpool. O objetivo do trabalho é definir melhores geometrias através da parametrização das dimensões principais e da utilização de métodos numéricos num estudo mais detalhado e aprofundado. O método de desenvolvimento leva em conta todos os fatores que influenciam na dinâmica do sistema como a hidrodinâmica de dois corpos (plataforma e corpo interno flutuante) e a dinâmica do gerador de energia (tipo de gerador e seu impacto no amortecimento do sistema global). / The continued use of fossil fuels has proved harmful for years, besides being a means finite energy. For this reason, the current and future demand for clean energy systems are great. Although there are already several structures dedicated to extracting energy from the sea, the concept on which it intends to work is innovative and with local technology. This theme has been already developed in a theoretical approach by the student of naval engineering Daniel Prata Vieira and his classmate Ana Luisa Orsolini, such as Final Paper Course of Naval Architecture and Ocean Engineering from the Escola Politécnica of USP, directed by Prof. Dr. André Luis Condino Fujarra. Vieira \\& Orsolini (2010) [1] studied in a different way the theme of energy generation from ocean waves, bringing up the use of already established monocolumn platform - prototype that earned several inventor of the year from Petrobras awards, besides patent, to the Numerical Offshore Tank, laboratory of the Naval Engineering Department of Poli - USP. The work of students Daniel and Ana was also recognized nationally getting the Petrobras Technology Award 2011 in the Energy Technology theme. The continuation of this work is to bring the background some important points related to platform design to optimize power generation through the relative motion between it and an internal floating body into moonpool. The objective is to define best geometries through the parameterization of the key dimensions and the use of numerical methods in a more detailed and in-depth study. The development method takes into account all the factors that influence the dynamics of the system such as the hydrodynamics of two bodies (platform and floating internal body) and the dynamics of the generator (type of generator and its impact on the damping of the global system).

O uso contínuo de combustíveis fósseis já se mostrou deletério há anos, além de ser um meio energético finito. Por este motivo, a demanda atual e futura por sistemas de energia limpa é grande. Muito embora já existam diversas estruturas dedicadas a extrair energia do mar, o conceito em que se pretende trabalhar é inovador e de tecnologia nacional. Este tema foi desenvolvido inicialmente em uma abordagem teórica pelo então aluno de engenharia naval Daniel Prata Vieira e sua colega Ana Luísa Orsolini, como Trabalho Final do curso de Engenharia Naval e Oceânica da Escola Politécnica da USP, orientados pelo Prof. Dr. André Luis Condino Fujarra. Vieira & Orsolini (2011) [1] abordaram de uma forma diferente o tema de geração de energia por ondas do mar, trazendo à tona o uso da já consagrada plataforma monocoluna - protótipo que rendeu diversos prêmios de inventor do ano da Petrobrás, além de patente, ao Tanque de Provas Numérico, laboratório do departamento de engenharia naval da POLI-USP. O trabalho dos alunos Daniel e Ana também foi reconhecido nacionalmente recebendo o Prêmio Petrobras de Tecnologia 2011 no tema de Tecnologia de Energia. A continuação do trabalho consiste em levar a fundo alguns pontos importantes relacionados ao dimensionamento da plataforma para otimizar a geração de energia através do movimento relativo entre ela e um corpo flutuante interno ao seu moonpool. O objetivo do trabalho é definir melhores geometrias através da parametrização das dimensões principais e da utilização de métodos numéricos num estudo mais detalhado e aprofundado. O método de desenvolvimento leva em conta todos os fatores que influenciam na dinâmica do sistema como a hidrodinâmica de dois corpos (plataforma e corpo interno flutuante) e a dinâmica do gerador de energia (tipo de gerador e seu impacto no amortecimento do sistema global). / The continued use of fossil fuels has proved harmful for years, besides being a means finite energy. For this reason, the current and future demand for clean energy systems are great. Although there are already several structures dedicated to extracting energy from the sea, the concept on which it intends to work is innovative and with local technology. This theme has been already developed in a theoretical approach by the student of naval engineering Daniel Prata Vieira and his classmate Ana Luisa Orsolini, such as Final Paper Course of Naval Architecture and Ocean Engineering from the Escola Politécnica of USP, directed by Prof. Dr. André Luis Condino Fujarra. Vieira \\& Orsolini (2010) [1] studied in a different way the theme of energy generation from ocean waves, bringing up the use of already established monocolumn platform - prototype that earned several inventor of the year from Petrobras awards, besides patent, to the Numerical Offshore Tank, laboratory of the Naval Engineering Department of Poli - USP. The work of students Daniel and Ana was also recognized nationally getting the Petrobras Technology Award 2011 in the Energy Technology theme. The continuation of this work is to bring the background some important points related to platform design to optimize power generation through the relative motion between it and an internal floating body into moonpool. The objective is to define best geometries through the parameterization of the key dimensions and the use of numerical methods in a more detailed and in-depth study. The development method takes into account all the factors that influence the dynamics of the system such as the hydrodynamics of two bodies (platform and floating internal body) and the dynamics of the generator (type of generator and its impact on the damping of the global system).