Orientador: Luiz Otávio Saraiva Ferreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-23T05:25:00Z (GMT). No. of bitstreams: 1 Gasparoto_HenriqueFagundes_M.pdf: 20120157 bytes, checksum: 1a0b108d3b6380d0ca446e17b2bc749b (MD5) Previous issue date: 2013 / Resumo: Motivado pelo projeto de dispositivos magnetomecânicos, este trabalho consiste na modelagem e simulação macroscópicas de corpos constituídos de materiais magnéticos, em frequência nula, representados por arranjos de dipolos magnéticos elementares em interação mútua, baseando se no método das fontes equivalentes (ESM, Equivalent Source Methods). O objetivo de modelagem e simulação se divide basicamente: na determinação do campo magnético - inclusive com o traçado das linhas de indução magnética; na determinação da força magnética e na obtenção do torque magnético sobre os corpos. A solução da força magnética e do torque magnético garante o elo de interação do magnetismo com a mecânica, permitindo assim o estudo de dispositivos magnetomecânicos tais como acoplamentos e mancais magnéticos passivos. Os corpos contemplados no estudo são do tipo ímã permanente ferromagnético mole paramagnético ou diamagnético. Um simulador denominado DipMag foi implementado em MATLAB®. Casos de sistemas magnetostáticos foram reproduzidos para a validação do simulador. Foram considerados sistemas com modelos algébricos, um sistema com modelo fenomenológico, e sistemas com modelos numéricos, inclusive com o uso do software FEMM. Constam casos como a determinação da força e torque magnético entre ímãs paralelepipedais, atração entre ímã e corpos ferromagnético mole e paramagnéticos, e a repulsão entre ímã e corpo diamagnético. Em especial, na modelagem e simulação para comparação com o caso experimental, onde um ímã paralelepipedal foi utilizado, obteve-se a polarização magnética equivalente com o uso de um medidor de campo magnético (Gaussmeter ou Teslameter) juntamente com formulação analítica (modelo de Coulomb). Diante das comparações o simulador DipMag foi bem sucedido na determinação do campo magnético externamente aos corpos, na obtenção da força magnética e do torque magnético sobre os corpos. Tendo em vista a forma adotada de representação magnética dos corpos, com a discretização em dipolos magnéticos dispostos em esferas, espera-se que o simulador DipMag possa evoluir da simulação estática para a simulação dinâmica, inclusive com acoplamento a métodos de partículas (por exemplo o DEM, Discrete Element Method). Contudo, espera-se ainda que, no futuro, o desempenho do DipMag seja melhorado com o uso do FMM (Fast Multipole Method) e com o processamento paralelo em GPU's / Abstract: Aiming magnetomechanical devices projects, this master thesis approaches the modeling and macroscopic simulation of bodies composed by basic magnetic materials at null frequency, represented by arrays of elementary magnetic dipoles in mutual interaction, based on the equivalent sources method (ESM). The objectives are: determination of the magnetic field - including mapping of magnetic induction lines, and computation of force and magnetic torque on bodies. The solution of force and magnetic torque ensures the interaction bond between magnetism and mechanics, allowing the study of magnetomechanical devices such as passive magnetic bearings and couplings. The kinds of materials included in this study are: permanent magnets, soft ferromagnetic, paramagnetic or diamagnetic. A simulator called DipMag was implemented in MATLAB®. Cases of magnetostatic systems were reproduced to validate the simulator. Were considered: systems with algebraic models, phenomenological models and numerical models, including the use of the FEMM simulator. Were studied the determination of force and magnetic torque between parallelepipedal magnets, the attraction between a magnet and a soft ferromagnetic and a paramagnetic bodies, and repulsion between a magnet and a diamagnetic body. When in modeling and simulating for comparing our method to the experimental case where a parallelepipedal magnet was used, its equivalent magnetic polarization was calculated from measumerents using a magnetic field meter (Teslameter or Gaussmeter) together with analytical formulation (Coulombian model). Our DipMag simulator was successful on determining magnetic field outside the bodies, obtaining the magnetic force and torque on the magnetic bodies. The method used for representing the magnetic bodies by magnetic dipoles in spheres, opens a pathway for DipMag simulator evolution, from static simulation to dynamic simulation, including the coupling with particle methods like DEM (Discrete Element Method). And it is expected that the DipMag simulator performance can be improved by using FMM (Fast Multipole Method) with parallel processing on GPU's (Graphics Processing Unit) / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica

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In this thesis, patterning methods to fabricate various functional particle patterns on substrates were developed, with the main aim of modifying the properties and functions of the substrates. Two classes of model substrates were selected; topographically patterned and smooth substrates. For the first model system, i.e., topographically patterned substrates, replication molding was used to topographically pattern substrates of different materials. The topographically patterned substrates, including TiO2, block-copolymer substrates (PS-b-P2VP and PS-b-P4VP), and microrings (TiO2 and Au), were then used to assemble silica (SiO2) microparticles for functional applications. By the assembly of microparticles on topographically patterned substrates, the wettability of the former could be reversibly switched from hydrophobic to hydrophilic. Moreover, a platform for the preparation of Janus particles by orthogonal functionalization of the top and bottom sides of microparticles assembled on topographically patterned substrates was developed. Clusters of superparamagnetic nanoparticles were stamped on the second class of model substrates, i.e., smooth silanized silicon substrates. A capillary stamping approach combined with an external permanent magnetic field or electromagnets was realized to print magnetic nanoparticle-based inks. In this way, ordered arrays of clusters of magnetic nanoparticles were produced.