Este trabalho visa estudar o fluxo de um fluido em um meio poroso (fibroso) durante o processo de Moldagem por Transferência de Resina (RTM) utilizando e comparando dois softwares comerciais: o ANSYS CFX, software de simulação numérica CFD não-dedicado a RTM, e o PAM-RTM, software de simulação numérica dedicado a esta aplicação. Foram utilizados dados experimentais, empregando uma pré-forma de tecido (0/90) de fibra de vidro e que foi impregnada por um óleo vegetal em injeção radial de RTM. Diversos experimentos foram realizados variando-se a pressão de injeção e o teor volumétrico de fibras a fim de observar o efeito no comportamento do fluxo. Com estes dados, alimentou-se o ANSYS CFX e o PAM-RTM utilizando equações dos meios porosos conhecidas, e foram feitas análises numéricas de todos os casos experimentais. Resultados de permeabilidade, viscosidade do fluido, tempo de preenchimento do molde, campo de pressão, variação da fração volumétrica das fases presentes e vetor velocidade de fluxo são apresentados e analisados. Concluiu-se que há uma sólida relação entre o experimental e o simulado (erros inferiores a 10%), o software PAM-RTM possui menor erro do que o ANSYS CFX quando comparados aos resultados experimentais, mas este último apresenta maior versatilidade de análises. / This work aims to study the flow of fluid through a porous (fibrous) media that occurs during Resin Transfer Molding (RTM) of composite materials and to compare it with the numerical results obtained with two commercial simulation software, ANSYS CFX, a general-use CFD package, and PAM-RTM, which is dedicated to RTM modeling. Experimental data were produced using a glass-fiber cloth (0/90) perform, which was impregnated with a vegetable oil in an RTM radial infiltration. Several experiments were performed varying injection pressure and fiber volume content in order to observe their effect on the flow behavior. These data were input into ANSYS CFX and PAM-RTM using known porous media equations and they were used to model all experiments. Results of permeability, fluid viscosity, mold filling time, pressure field, variation of volume fraction of the phases and the flow velocity vector are presented and analyzed. An excellent correlation between experimental and simulated results was found (errors less than 10%), and PAM-RTM yielded smaller error than ANSYS CFX, but the latter allows greater flexibility.

Este trabalho visa estudar o fluxo de um fluido em um meio poroso (fibroso) durante o processo de Moldagem por Transferência de Resina (RTM) utilizando e comparando dois softwares comerciais: o ANSYS CFX, software de simulação numérica CFD não-dedicado a RTM, e o PAM-RTM, software de simulação numérica dedicado a esta aplicação. Foram utilizados dados experimentais, empregando uma pré-forma de tecido (0/90) de fibra de vidro e que foi impregnada por um óleo vegetal em injeção radial de RTM. Diversos experimentos foram realizados variando-se a pressão de injeção e o teor volumétrico de fibras a fim de observar o efeito no comportamento do fluxo. Com estes dados, alimentou-se o ANSYS CFX e o PAM-RTM utilizando equações dos meios porosos conhecidas, e foram feitas análises numéricas de todos os casos experimentais. Resultados de permeabilidade, viscosidade do fluido, tempo de preenchimento do molde, campo de pressão, variação da fração volumétrica das fases presentes e vetor velocidade de fluxo são apresentados e analisados. Concluiu-se que há uma sólida relação entre o experimental e o simulado (erros inferiores a 10%), o software PAM-RTM possui menor erro do que o ANSYS CFX quando comparados aos resultados experimentais, mas este último apresenta maior versatilidade de análises. / This work aims to study the flow of fluid through a porous (fibrous) media that occurs during Resin Transfer Molding (RTM) of composite materials and to compare it with the numerical results obtained with two commercial simulation software, ANSYS CFX, a general-use CFD package, and PAM-RTM, which is dedicated to RTM modeling. Experimental data were produced using a glass-fiber cloth (0/90) perform, which was impregnated with a vegetable oil in an RTM radial infiltration. Several experiments were performed varying injection pressure and fiber volume content in order to observe their effect on the flow behavior. These data were input into ANSYS CFX and PAM-RTM using known porous media equations and they were used to model all experiments. Results of permeability, fluid viscosity, mold filling time, pressure field, variation of volume fraction of the phases and the flow velocity vector are presented and analyzed. An excellent correlation between experimental and simulated results was found (errors less than 10%), and PAM-RTM yielded smaller error than ANSYS CFX, but the latter allows greater flexibility.

Historicamente, o sistema para instalação de equipamentos de produção submarina de petróleo por meio de cabos guia, tem sua eficiência comprovada. Porém a grande maioria dos projetos das bases guia submarinas foi calculada por métodos analíticos, que embora permitam a obtenção de respostas exatas em todos os infinitos pontos de uma estrutura, não são aplicáveis a todos os casos. Isso motivou a aplicação do método dos elementos finitos (MEF) neste trabalho, que a partir do desenvolvimento de procedimentos aproximados, pode ser aplicado independentemente da forma da estrutura e das condições de carregamento. O estudo consiste da análise estrutural do modelo tridimensional da estrutura da base guia, modelado no software Autodesk Inventor e analisado no software ANSYS Workbench. O estudo traz uma pesquisa diagnóstica e utiliza abordagem quantitativa e exploratória. Diferentes modelos matemáticos foram gerados para obtenção dos resultados nos pontos mais críticos da estrutura, a fim de se determinar sua resistência aos esforços de instalação e operação aplicados, levando em consideração os critérios estabelecidos nas normas DNV No. 2.7-3, API 17D 1.ed. e a tensão equivalente de von-Mises. / Historically, the guideline system for installation of subsea oil production equipment has proven its efficiency. However the majority of the subsea guide base designs have been calculated by analytical methods, although they allow obtaining exact answers in all infinite points of a structure, they are not applicable to all cases. This motivated the application of the finite element analysis method (FEA) in this work, which from the development of approximate procedures can be applied regardless of the structure shape and loading conditions. This paper consists of a structural analysis of the guide base frame model, generated in Autodesk Inventor software and analyzed in ANSYS Workbench software. This study brings a diagnostic research using a quantitative and exploratory approach. Different mathematical models were generated to obtain the results at the most critical points of the structure in order to determine its resistance to the loads applied during installation and operation, taking into account the criteria laid down in DNV No. 2.7-3, API 17D 1st Ed. and the von-Mises equivalent stress.

It is well known that surface tension of a liquid has a decisive role in flow dynamics and the eventual equilibrium state, especially in confined flows under low gravity conditions and also in free surface flows. One such instance of a combination of these two cases where surface tension plays an important role is in the microgravity environment of a spacecraft propellant tank. In this specific case both propellant acquisition and residual propellant estimation are critical to the mission objectives particularly in the end-of-life phase. While there have been a few studies pertaining to the equilibrium state in given geometric configurations, the transient flow leading to final state from an initial arbitrary distribution of propellant is rarely described. The present study is aimed at analysing the dynamic behaviour of the liquids under reduced gravity through numerical simulation and also addresses the specific case of propellant flow transient in a cone-in-a-sphere type of tank configuration proposed by Lal and Raghunandan which is likely to result in both improved acquisition and life time estimation of spacecraft. While addressing this specific problem, the present work aims to study the transient nature of such surface tension driven flows in a general form as applicable to other similar problems also. Volume of Fluid (VOF) method for multiphase model in ANSYS FLUENT was adapted with suitable changes for generating numerical solutions to this problem. Simulations were run for three different cone angles of 17o, 21o & 28o with a flat liquid surface for full scale models to measure the rise height and time of rise. Two scaled models of ½ and 1/10th of the original dimensions with the same liquid configuration of the 28o cone angle case were simulated to see if the time scales involved would come down for experimental feasibility. A third simulation of the 1/10th scale model was run with the liquid spread in the tank to imitate the general conditions found in the propellant tank in microgravity. To understand the behaviour of liquids in the microgravity state to changing physical parameters, a set of simulations was run using liquid phases as water and hydrazine with different physical parameters of temperature and surface tension. The theory put forward by Lal and Raghunandan was found to stand firm. In the case of the cone angle of 28o it was observed that in the final equilibrium state the liquid collected towards the apex of the cone with the larger volume fraction of liquid accumulating inside the cone. An addition of a cylindrical section at the bottom of the cone seems to help although not uniformly for all case. The equilibrium settling times for all the three cone angle cases were in the order of 300 to 600 seconds for simulations on a spherical tank of diameter two metres which was close to the actual tank dimension used on spacecraft. Scaled down simulations of 1/10th and ½ the tank geometry with both flat liquid surfaces and spread out liquid volumes showed that the smaller models had equilibrium settling times which were considerably lower (in the order of tens of seconds) than the full scale models. Although smaller, these time scales are larger than the maximum time scales available in drop tower tests which provide a maximum free fall time of around 9 to 10 seconds. Validation of the proposed configuration by flying an aircraft in a parabolic flight path is a possibility that could be explored for the scaled down models since the zero-g duration for these flights is on an average between 15-20 seconds.

Microbubble drag reduction (MBDR) is an effective method to improve the efficiency of fluid systems. MBDR is a field that has been extensively studied in the past, and experimental values of up to 80% to 90% drag reduction have been obtained. The effectiveness and simplicity of MBDR makes it a viable method for real world applications, particularly in naval applications where it can reduce the drag between the surface of ships and the surrounding water. A two dimensional single phase model was created in ANSYS Fluent to effectively model the behavior of bubble laden flow over a flat plate. This model was used to analyze the effectiveness of MBDR based on the following factors: Reynolds number, types of gas injected, upstream flow velocity, upstream fluid type, density ratio, flow rate of injected gas, using air as the upstream injected fluid.

Chassis is the primary structural component of an automobile. It is the main supporting structure of a vehicle to which all other systems like braking, suspension and differential are attached. In this thesis, a methodology for L7e category vehicle chassis design and structural stability analysis is presented. The present car being developed at Uniti Sweden AB is classified as L7e category vehicle as per the European Union, therefore the chassis developed in this thesis considers the specific characteristics that vehicles under this category demands for. A literature study is carried out to review various existing designs of vehicle chassis, latest innovations and advanced materials used to manufacture the same. The various types of forces and stresses commonly acting on chassis structures are analyzed and their effects on the vehicle is understood. After completing literature study, several findings are listed in a systematic manner, by providing ample arguments to justify each of them. The pro-con analysis is conducted to evaluate merits and demerits of each alternative type of chassis and the material to manufacture it. The most essential design criteria are derived from the QFD (Quality function deployment) which then acts as important guidelines during the actual design process. Structural chassis frame is designed as per the design criteria, using the CAD software CATIAV5R19 and the structural stability of the same is tested and analyzed using ANSYS 15.0 software. From the results of these analysis tests the static structural stability of the design is confirmed.

This master's thesis deals with the design of FEM model of gear pair with an intention to find out how stiffness changes during meshing. It firstly describes the necessary knowledge needed to analyse the problem, like the geometry of an involute tooth and evaluation of meshing stiffness. Followed by a description of work procedures from the creation of models through settings of mesh, contacts and analysis to evaluating of results.

This master thesis deals with passive compensation of a thermal deformation for a binder of portal machining center. The problem is solved by computational modeling with finite element method using ANSYS Workbench software. Afterwards mathematical optimization (also using ANSYS Workbench software) is used for finding binder parameters in order to reduce thermal deformation and its weight. The output is two new versions of binder which are compared to the original configuration.

Diploma thesis named CFD simulation of the steam flow in the unregulated extraction of the steam turbine is about an analysis of the balance piston impact on the area of the steam turbine, where the extraction is located. First part describes basic knowledge of the steam turbine in general. At the end of this chapter, there is a description of the solved steam turbine. Next chapter is about introduction to the CFD. Practical part deals with a construction of 3D models, meshing and setting of the boundary conditions in the program ANSYS CFX. The main part of this thesis summarizes the results of the CFD simulation and stipulates the temperature range on the extraction pipe. In conclusion, there is a recommendation how to determine design temperature of the extraction pipe influenced by the balance piston.

This thesis deals with analyses of thermoplastic welded joints. Experiments were performed, in which the not-welded specimens and specimens with cruciform welded joints were tested by tensile and three-point bending test. For these measurements, polypropylene and polyethylene specimens were used. Afterwards, the analyses of specimen models were made in the ANSYS programme. The results of the analyses were compared with figures of the analytic calculations and measurements.