1,721,020 research outputs found
Vibration studies of composite thin-walled curved box-beam using structural tailoring
Get PDFThis paper presents numerical study about the influence of different types of configurations of composite material son the dynamic response of box curved beams.Fil: Piovan, Marcelo Tulio. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cortínez, Víctor Hugo. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Determinación de propiedades mecánicas y eléctricas de polímeros conductores empleados en impresión 3D
No full textEn este trabajo se estudian las propiedades estructurales y eléctricas de componentes impresos hechos con polímeros conductores. Debido a la anisotropía de las impresiones 3D, existe una sensibilidad a la variación de los parámetros de impresión entre los que se enumeran espesor de capa, la temperatura de plataforma y boquilla, ángulo de impresión, dirección de construcción, etc. Otros aspectos que tienen injerencia en la conductividad de los productos resultantes son el ancho y la longitud de las tiras impresas. Se coteja la variación de estas propiedades eléctricas y mecánicas en general respecto de parámetros de impresión y diseño.Fil: Diaco, Franco. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; ArgentinaFil: Nacud, Carlos. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; ArgentinaFil: Piovan, Marcelo Tulio. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina18º Congreso Internacional de Metalurgia y MaterialesSan Carlos de BarilocheArgentinaSociedad Argentina de Materiale
Un elemento finito espectral para vigas de paredes delgadas construidas con materiales compuestos
Get PDFEn este artículo se desarrolla un elemento finito espectral para vigas de paredes delgadas construidas con materiales compuestos. En primer lugar se describe la teoría de vigas de paredes delgadas de materiales compuestos sobre la base de modelos que consideran la flexibilidad por corte completa, desarrollados previamente por los autores. Luego, se obtienen las funciones de forma espectrales y se plantea la matriz del elemento finito espectral para finalmente efectuar estudios de validación del elemento obtenido.Fil: Piovan, Marcelo Tulio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; ArgentinaFil: Cortínez, Víctor Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentin
Vibration and buckling of composite thin-walled beams with shear deformability
Get PDFIn this paper, a theoretical model is developed for the dynamic analysis of composite thin-walled beams with open or closed cross-sections. The present model incorporates, in a full form, the shear flexibility (bending and warping shear) as well as a state of initial stresses. This allows to study the free vibration and buckling problems in a unified fashion. An analytical solution of the developed equations is obtained for the case of simply supported thin-walled beams. Numerical examples are given to demonstrate the importance of the shear flexibility on the vibration and buckling behavior of the considered structures.Fil: Cortínez, Víctor Hugo. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piovan, Marcelo Tulio. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentin
Transverse shear deformability in the dynamics of thin-walled composite beams: consistency of different approaches
Get PDFThe aim of this work is to describe an analysis of the transverse shear deformation in the dynamics of thin-walled composite beams. Some thin-walled-composite-beam models, which are derived by means of different approaches (principle of virtual works and principle of Hellinger-Reissner among others), show substantial discrepancies due to the employment of different consitutive equations based on the aforementioned approaches. In the following paragraphs a comparison of different schemes and hypotheses related to constitutive equations for thin-walled composite beams is performed.Fil: Piovan, Marcelo Tulio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; ArgentinaFil: Cortínez, Víctor Hugo. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentin
Vibrations of axially moving flexible beams made of functionally graded materials
Get PDFProblems related to the vibrations of axially moving flexible beams made of functionally graded materials are addressed. The problem of an axially moving beam may be interpreted as a telescopic system in which the mass is not constant, the mechanism of elastic deformation is transverse bending. A thin-walled beam with annular cross-section is analyzed, in which a continuously graded variation in the composition of ceramic and metal phases across the wall thickness with a simple power law is considered. In this paper a finite element scheme is employed to obtain numerical approximations to the variational equation of the problem. Normally, finite element approaches use fixed-size elements, however, for this kind of problems the increase of the number of elements, step by step as the mass enters, is a cumbersome task. For this reason an approach based on a beam-element of variable domain is adopted. The length of the element is a prescribed function of time. Results highlighting the effects of the beam flexibility, tip mass and material constituents on the dynamics of the axially moving beams are presented and the corresponding conclusions are given.Fil: Piovan, Marcelo Tulio. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; ArgentinaFil: Sampaio, Rubens. Pontifícia Universidade Católica do Rio de Janeiro; Brasi
Out-of-plane vibrations of shear deformable continuous horizontally curved thin-walled beams
Get PDFThis paper presents numerical study about the influence of the shear flexibility, due to either bending and warping, on the out-of-plane free vibration of continuous horizontally curved thin-walled beams with both open and closed sections. This study was made by means of a recently developed finite element formulation for shear deformable curved thin-walled beams. The model is briefly reviewed and is used to obtain natural frequencies of continuous I-beams and box beams. A parametric study was performed in order to elucidate the influence of shear deformability, on the dynamic behavior of continuous thin-walled curved beams, for different slenderness ratios, cross-sectional characteristics and boundary conditions.Fil: Piovan, Marcelo Tulio. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; ArgentinaFil: Cortínez, Víctor Hugo. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; ArgentinaFil: Rossi, Raul Edgardo. Universidad Nacional del Sur. Departamento de Ingeniería; Argentin
Nonlinear dynamics of rotating box FGM beams using nonlinear normal modes
Get PDFIn this work an analysis is performed on the nonlinear planar vibrations of a functionally graded beam subjected to a combined thermal and harmonic transverse load in the presence of internal resonance. Adopting the direct perturbation MMS technique, the partial differential equations of motion of the beam are reduced to sets of first-order nonlinear modulation equations in terms of the complex modes of the beam. The assumption of steady-state values of centrifugal loads is evaluated. It has to be said that there is a lack of information about modeling of rotating box beams made of functionally graded materials (FGMs) under thermo-mechanical loads. The influence of the transverse load amplitude and the internal detuning parameter on the strength of nonlinear modal interaction is illustrated. It is also shown that the system exhibits periodic and quasiperiodic responses for a typical range of parameter values.Fil: Machado, Sebastián Pablo. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahia Blanca; ArgentinaFil: Piovan, Marcelo Tulio. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahia Blanca; Argentin
Stability of composite thin-walled beams with shear deformability
Get PDFIn this paper, a theoretical model is developed for the stability analysis of composite thin-walled beams with open or closed cross-sections. The present model incorporates, in a full form, the shear flexibility (bending and non-uniform warping), featured in a consistent way by means of a linearized formulation based on the Reissner's Variational Principle. The model is developed using a non-linear displacement field, whose rotations are based on the rule of semi-tangential transformation. This model allows to study the buckling and lateral stability of composite thin-walled beam with general cross-section. A finite element with two-nodes and fourteen-degrees-of-freedom is developed to solve the governing equations. Numerical examples are given to show the importance of the shear flexibility on the stability behavior of this type of structures.Fil: Cortínez, Víctor Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; ArgentinaFil: Piovan, Marcelo Tulio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentin
A 1D model for the dynamic analysis of magneto-electro-elastic beams with curved configuration
No full textThe scope of the present paper is to present some new contributions in the dynamics of curved/straight MEE beams. The structure consists of a curved beam constructed with ceramic/metallic materials whose elastic behavior can be modified by influence of electro-magnetic fields. The problem of coupled elastic, electric and magnetic fields is briefly explained and the motion equations for curved members are introduced. An equivalent model for a MEE curved beam is then deduced appealing to a few constitutive hypotheses that enable the derivation of the electric–magnetic fields acting on the beam in preferential and prescribed directions. The theoretical topics covered in the model include shear flexibility due to bending as well as coupled elastic-electro-magnetic terms, among others. The model can be reduced to other models (straight beams or curved beams) by dropping terms or the magneto-electric fields and/or geometric parameters. Comparisons with the available models (for the reduced case of straight beam) and 2D models evaluated in the context of finite element methodologies are presented as well.Fil: Piovan, Marcelo Tulio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad de las Fuerzas Armadas. Departamento de Ciencias de la Energía y Mecánica; Ecuador. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Olmedo Salazar, José Fernando. Universidad de las Fuerzas Armadas. Departamento de Ciencias de la Energía y Mecánica; Ecuado
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