32-54 METODĂ HIBRIDĂ DE STUDIU PENTRU ORICE TIP DE SECȚIUNE SUPUSĂ LA TORSIUNE
A HYBRID MeTHOD OF STUDY FOR ANY SECTION
TYPE UNDER TORSIONAL LOADING
This paper presents a methodology regarding the numerical analysis of any section type under torsion loading. This methodology is named a hybrid one, because it practically consist in using of the membrane analogy – an experimental method – but the solving and result analysis are made by Finite Element Method (FEM). In the modelling of a structure, of a beam, applying of the torsion moment involves some difficulties especially regarding of the local stress concentration. By the methodology presented in this paper, the analysis of the shear stress field can be made with a great accuracy using FEM, without any experimental means. This methodology takes into account all the physical significations of the membrane analogy and all these are evaluated by FEM. That require of the pressure-effort ratio to be -2 is made by a thermal loading, cooling the membrane. By post-processing, the numerical result analysis can be quickly and easily made. The modelling presented in this paper can be used for any section type: whatever the shape, no matter if the section has one or more holes etc. By this methodology, the membrane analogy becomes more efficient, more versatile and more accessible for any section type.
Keywords: torsion, membrane analogy, finite elements
Cuvinte cheie: torsiune, analogia cu membrana, elemente finite