In this thesis, a hybrid-stress finite element is developed for nonuniform Timoshenko beams. The element stiffness matrix is obtained by assuming a stress field only. Since element boundaries are simply the element nodes, a displacement assumption is not necessary. Geometric and mass stiffness matrices are obtained via equilibrium and kinematics of deformation equations which are derived in the beam arbitrary cross-section. Utilizing this method eliminates the displacement assumption for the geometric and mass stiffness matrices. The element has six degrees of freedom at each node. Axial, flexural and torsional effects are considered. The torsional and distortional warping effects are omitted. Deformations due to shear is also taken into account. Finally, some sample problems are solved with the element and results are compared with the solutions in the literature and commercial finite element programs (i.e. MSC/NASTRAN&reg / ).

This doctoral research project aims the study of finite element methods discretized in dynamic meshes in order to simulate fluid-solid interaction and multiphase flow phenomena, particularly flows involving phenomena that are most significant in microfluidic and biofluidic applications. The equations that model multiphase flow will be treated in an arbitrary Lagrangian-Eulerian framework, when required, with several types of boundary conditions at the interfaces, depending on the nature of the phases. The numerical challenges found in this application range from the correct representation of the interface between fluids, passing through geometric challenges in the maintainability of the computer mesh, to the challenges posed by microscales. Special attention is given to squimer models, by means of a general formulation of the swimming problem as well as the steps to transform a standard fluid-solid model to a squirming model. / Este projeto de pesquisa de doutorado visa o estudo de métodos de elementos finitos discretizados em malhas dinâmicas, com o objetivo de simular fenómenos de interação fluídoestrutura e escoamentos multifásicos, em especial escoamentos que envolvem aplicações em microfluídica e biofluídica. As equações que modelam escoamentos multifásicos serão tratadas em um referencial lagrangeano-euleriano arbitrário, quando requerido, com differentes tipos de condições de contorno nas interfaces, dependendo da natureza das fases. Os desafios numéricos impostos por esta aplicação vão desde a correta representação das interfaces, passando por desafios geométricos na manutenibilidade da malha computacional, até os desafios impostos pelas escalas microscópicas. Atenção especial é dada aos modelos de squimer, por meio de uma formulação geral do problema de natação, bem como os passos para transformar um modelo fluido-sólido padrão em um modelo de squirming.

This diploma thesis is focused on the construction proposal of pallet hoist connected with powered section roller conveyor for transportation of europallets with loads 1200 kg. The proposed hoist is designed for vertical handling between two working positions with the distance 5 meters. The thesis contains all structural units of machine, design of all standars parts and control calculation of some parts using the finite element method (FEM). The thesis contains complete drawing documentation for designed machine.