The Experts below are selected from a list of 3612 Experts worldwide ranked by ideXlab platform
Enrique Hernandezmontes - One of the best experts on this subject based on the ideXlab platform.
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approximate expression of the prandtl Membrane Analogy in linear elastic pure torsion of open thin walled cross sections and regular polygons
International Journal of Solids and Structures, 2021Co-Authors: Luisa Maria Gilmartin, Antonio Palomares, Enrique HernandezmontesAbstract:Abstract This paper presents a new general methodology to obtain an approximate analytical expression of the Saint-Venant's torsion. The shear stress in each of the principal Cartesian directions is obtained by the derivation of the stress function, whose analytical expression is obtained from the Prandtl Analogy. The proposed methodology uses two variables quadratic piecewise functions to define the Prandtl Membrane. This document shows that the approximate procedure is especially suitable for steel shapes, giving values very close to those obtained with more precise methods. The main advantage of the presented methodology is its simplicity, which makes it useful for both pedagogic and practical applications. Several examples are developed.
Gianni Royer-carfagni - One of the best experts on this subject based on the ideXlab platform.
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Membrane Analogy for multi-material bars under torsion.
Proceedings. Mathematical physical and engineering sciences, 2019Co-Authors: Laura Galuppi, Gianni Royer-carfagniAbstract:Prandtl's Membrane Analogy for the torsion problem of prismatic homogeneous bars is extended to multi-material cross sections. The linear elastic problem is governed by the same equations describing the deformation of an inflated Membrane, differently tensioned in regions that correspond to the domains hosting different materials in the bar cross section, in a way proportional to the inverse of the material shear modulus. Multi-connected cross sections correspond to materials with vanishing stiffness inside the holes, implying infinite tension in the corresponding portions of the Membrane. To define the interface constrains that allow to apply such a state of prestress to the Membrane, a physical apparatus is proposed, which can be numerically modelled with a two-dimensional mesh implementable in commercial finite-element model codes. This approach presents noteworthy advantages with respect to the three-dimensional modelling of the twisted bar.
Luisa Maria Gilmartin - One of the best experts on this subject based on the ideXlab platform.
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approximate expression of the prandtl Membrane Analogy in linear elastic pure torsion of open thin walled cross sections and regular polygons
International Journal of Solids and Structures, 2021Co-Authors: Luisa Maria Gilmartin, Antonio Palomares, Enrique HernandezmontesAbstract:Abstract This paper presents a new general methodology to obtain an approximate analytical expression of the Saint-Venant's torsion. The shear stress in each of the principal Cartesian directions is obtained by the derivation of the stress function, whose analytical expression is obtained from the Prandtl Analogy. The proposed methodology uses two variables quadratic piecewise functions to define the Prandtl Membrane. This document shows that the approximate procedure is especially suitable for steel shapes, giving values very close to those obtained with more precise methods. The main advantage of the presented methodology is its simplicity, which makes it useful for both pedagogic and practical applications. Several examples are developed.
Francisco J Arnaiz - One of the best experts on this subject based on the ideXlab platform.
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the Membrane Analogy for surface tension in liquids
Journal of Chemical Education, 1997Co-Authors: Francisco J ArnaizAbstract:The concept of surface tension is usually introduced by referring to liquids and comparing their surface with a thin film that requires some effort to be perforated. That surfaces have special properties is easily assumed by students since it is obvious that surface particles interact with the surrounding in a different way than those inside. However, students frequently have trouble envisioning the surface of a liquid to be like a thin Membrane. To reinforce the Membrane Analogy for surface tension two simple experiments, easily performed with kitchen products, are suggested.
Laura Galuppi - One of the best experts on this subject based on the ideXlab platform.
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Membrane Analogy for multi-material bars under torsion.
Proceedings. Mathematical physical and engineering sciences, 2019Co-Authors: Laura Galuppi, Gianni Royer-carfagniAbstract:Prandtl's Membrane Analogy for the torsion problem of prismatic homogeneous bars is extended to multi-material cross sections. The linear elastic problem is governed by the same equations describing the deformation of an inflated Membrane, differently tensioned in regions that correspond to the domains hosting different materials in the bar cross section, in a way proportional to the inverse of the material shear modulus. Multi-connected cross sections correspond to materials with vanishing stiffness inside the holes, implying infinite tension in the corresponding portions of the Membrane. To define the interface constrains that allow to apply such a state of prestress to the Membrane, a physical apparatus is proposed, which can be numerically modelled with a two-dimensional mesh implementable in commercial finite-element model codes. This approach presents noteworthy advantages with respect to the three-dimensional modelling of the twisted bar.