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Showing 1 to 20 of 30 for “"Cascas"”.
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Análise limite de cascas via otimização
Limit analysis of elastic-plastic structures is considered in general and in the particular case of shells. Numerical methods for limit analysis of rotationally symmetric shells are developed. Limit analysis is essentially a problem in optimization. Therefore the theory of plastic collapse is …
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Vibrações de cascas cilíndricas delgadas contendo fluido
The main theoretical and experimental results for the dynamic interaction occuring between fluid and thin cylindrical shells, which result from a strong coupling among the vibration modes, are presented herein. Emphasis is given to the used experimental techniques and obtained test results which …
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Vibrações e estabilidade paramétrica de cascas axissimétricas
The general problem of Dynamics of Elastic Bodies is presented, and the problems of dynamic response and stability of rotating axisyrnmetric shells, under a non-rotating load, are studied. Using a Fourier series expansion for the circunferential variable it is shown that this load generates a …
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Instabilidade e sensibilidade de cascas cilíndricas circunferencialmente enrijecidas
An analysis of the buckling load and the imperfection-sensitivity of ring stiffened cylinders under external pressure is presented. Koiter's general post-buckling theory provides the basis to estimate the imperfection-sensitivity by relating it to the initial post-buckling behavior of the perfect …
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Análise de cascas espessas com elementos finitos mistos
This paper presents the development of a mixed finite element for analysis of thick shells of arbitrary shape, in the most general case. The fundamental unknowns are stresses and displacements. The analysis is linear and is based on the Theory of Elasticity. The finite element at issue is a …
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Associação de cascas de revolução com carregamento axissimétrico
This work deals with the analysis of axissymmetrical shells by means of the available analytical solutions of spherical, conical and cylindrical elements. A similar approach to the finite element method is used, the difference being on the choice of the displacement functions that are the solutions …
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Um modelo matemático para estabilidade elástica de cascas cilíndricas enrijecidas
A mathematical model to investigate non-linear branching equilibrium paths of stringer stiffened cylindrical shells under axial compression is presented. This model is based on a general displacements solution of the dynamic non-linear differential equilibrium equations for an isotropic thin …
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Análise dinâmica linear de cascas axissimétricas com um elemento finito curvo
Linear dynamic analysis based on the theories of LOVE and FLÜGGE is presented for axisymmetric thin shells under the action of arbitrary loads including temperature effects. The general equilibrium equations and the corresponding boundary conditions are obtained from the Principle of Virtual work. …
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Elemento finito para placas e cascas usando a teoria de Kirchhoff-Love
The purpose of this work is to formulate a finjte-element for plates and shells using the theory of Kirchhoff-Love. ln arder to guarantee the continuity of rotations for the middle surface normal vectors, it was used Hermite interpolation functions for the transverse displacements and incomplete …
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Acomodação estrutural na associação de cascas axi-simétricas sujeitas a pressões internas
This work has the objective of determining the lower bound estimates of the shakedown pressure for flush radial cilinder-sphere intersections. Two elastic analysis methods were developed to find the stresses at the junction, where the most charged elements are situated. The shakedown pressure was …
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Métodos de elementos finitos mistos e malhas adaptativas na análise de cascas axissimétricas
Thin axissimetric shell studied through the use of Reissner-Mindlin theory presents some difficulties in constructing stable finite elements aproximations due to its dependence on the thickness of the shell. Classical single field as well as two fields finite element formulations are discussed. A …
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Elementos finitos para a análise limite de cascas axissimétricas via programação não-linear
This work is concerned with rigid-plastic limit analysis of shells of revolution subject to rotationally symmetric loadings. These shells, of arbitrary shape, are discretized into a series of finite elements, each being a conical shell. The von Mises condition, valid for sandwich shells, is used. …
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Um sistema computacional para a análise de cascas de revolução com irregularidades localizadas
This work presents the development of a finite element computer program, which is presently intended for the analysis of shells, and particularly of shells of revolution with local irregularities. In the analysis of these shells, the "classic" approach would be either to analyse the entire …
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Influência da interação entre modos e imperfeições na flambagem de cascas cilíndricas axialmente comprimidas
Results from a non-linear analysis of circular cylindrical shells under axial compression are presented. Included in this analysis are the effects that mode coupling and initial geometric imperfections have on the non-linear buckling behaviour. It is shown, through the inspection of energy …
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Avaliação de atividade antihepatotóxica de duas espécies vegetais popularmente conhecidas como "quina": Strychnos pseudoquina A. St. Hil. e Coutarea hexandra (Jacq.) K. Schum
… antihepatotóxico de extratos obtidos de cascas e folhas de duas espécies vegetais utilizadas popularmente com esta finalidade, as quinas Strychnos pseudoquina A. St.-Hil., família Loganiaceae, e Coutarea hexandra (Jacq.) K. Schum, família Rubiaceae. Foi realizada a prospecção fitoquímica …
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Análise dinâmica linear por superposição modal de cascas finas arbitrárias pelo Método dos Elementos Finitos
The main purpose of this work is to study the linear dynamic behavior of arbitrary thin shells by the Finite Element Method. Plane triangular elements with eighteen degrees of freedom each are used. The general equations of movement are obtained from the Hamilton Principle and solved by the Modal …
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Análise de cascas de revolução pelo método dos elementos finitos com elemento de casca axissimétrico
The static linear analysis of axi-symmetric shells under axially symmetric loading is done by the finite element method. For this purpose a truncated cone element is used to take advantage of the symmetry or the structure. Three interior degrees of freedom are introduced for each element, resulting …
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O método dos elementos finitos aplicado a problemas de cascas e estruturas laminares utilizando-se elementos triangulares planos
Analysis of general shells and folded plates by the Finite Element Method, with the use of a plane triangular finite element with fifteen and also with eighteen degrees of freedom. A brief exposition of the Method in which its variational characteristic is pointed, is made at the begining. The …
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Aproveitamento da farinha de casca de abacaxi Ananas comosus (L.) Merril para a elaboração de sorvete funcional probiótico
… por alternativas viáveis de reaproveitamento de cascas, talos, folhas e bagaços de frutas na alimentação humana. Somado a isto, o aumento do interesse pelo consumo de alimentos funcionais, como os probióticos, desperta o desenvolvimento de novos produtos que atendam as expectativas de saúde, …
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Análise comparativa dos critérios do código ASME, seção VIII Divisão l e Divisão 2, para tensões de cascas delgadas e de revolução, usando o Método dos Elementos Finitos
In view of the wide industrial use of Pressure Vessels, mainly in the petrochemical processes, their in strutural design optimization is becoming important. The aim of this work is the interpretation of the stresses calculated by the Finite Element Method, and to compare them with those of ASME …
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