Search results for "structural mechanic"
showing 6 items of 26 documents
YETI: YET another Iga code
2023
YETI is a library offering an implementation of IsoGeometric Analysis based on NURBS and B-Splines. It is published under the GNU Lesser General Public Licence and comes in the form of a Python library allowing the user to enter the input data of a NURBS arametrization (as a text file inspired from Abaqus input files syntax). Stiffness and mass matrices and right hand side vector are computed to form linear systems for solving mechanical or thermal problems. Solid or Kirchhoff-Love shell elements are available.In the context of shape optimization, a NURBS parametrization can be set up with design variables based on control points position. YETI can compute the analytical sensitivities [1] o…
Simulation numérique de la propagation d'une onde de choc issue d'une explosion en champ libre et son interaction avec un modèle biomécanique humain
2017
International audience; Les chargements liés à l’explosion sont fréquents dans le domaine militaire avec des conséquences plus ou moins sévères sur les structures en interaction avec cette sollicitation. Dans le contexte de protection du combattant, la compréhension de ce phénomène physique est important dans l’élaboration de systèmes de protection et pour prévenir les traumatismes liés aux chargements du "blast primaire". Dans ce contexte, ce papier décrit l’étude numérique d’une onde de souffle et son interaction avec un modèle biomécanique du corps humain, en utilisant les notions de similitudes
Sur la prise en compte de quelques conditions aux limites avec la méthode des éléments finis
2017
Ce cours a pour principal sujet la discrétisation de certaines conditions limites sur le bord d'un domaine à l'aide de la méthode des éléments finis. Nous étudions en particulier des problèmes elliptiques avec conditions de Dirichlet non-homogènes, puis avec conditions de Signorini. Les conditions de Signorini sont des conditions de contact unilatéral entre un solide et un support rigide. Différentes méthodes sont passées en revue, et nous détaillons l'analyse pour les méthodes classiques et celle de Nitsche.
Effect of the Time Dependent Loading of Type IV Cylinders using a Multiscale Model
2019
International audience; The current requirements for composite cylinders are still based on an arbitrary approach derived from the behaviour of metal structures, that the designed burst pressure should be at least 2.5 times the maximum in-service pressure [1]. This could lead to an over-designed composite cylinder for which the weight saving would be less than optimum. Moreover, predicting the lifetime of composite cylinders is a challenging task due to their anisotropic characteristics. A federal research institute in Germany (BAM) has proposed a minimum load-cycle requirement that mitigates this issue by using a Monte-Carlo analysis of the burst test results [2-3]. To enrich this study, m…
Pressure-Induced Deformation of Pillar-Type Profiled Membranes and Its Effects on Flow and Mass Transfer
2019
In electro-membrane processes, a pressure difference may arise between solutions flowing in alternate channels. This transmembrane pressure (TMP) causes a deformation of the membranes and of the fluid compartments. This, in turn, affects pressure losses and mass transfer rates with respect to undeformed conditions and may result in uneven flow rate and mass flux distributions. These phenomena were analyzed here for round pillar-type profiled membranes by integrated mechanical and fluid dynamics simulations. The analysis involved three steps: (1) A conservatively large value of TMP was imposed, and mechanical simulations were performed to identify the geometry with the minimum pillar density…
FRP reinforcement for concrete structures: state-of-the-art review of application and design
2014
Fiber reinforced polymers (FRPs) are considered to be a promising alternative to steel reinforcement, especially in concrete structures subjected to an aggressive environment or to the effects of electromagnetic fields. Although attempts to develop effective reinforcement have been followed, the application of FRPs remains limited by the solution to simple structural problems that mainly appear due to the absence of design codes, significant variation in the material properties of FRP composites and limited knowledge gained by engineers as regards the application aspects of FRP composites and structural mechanics of concrete elements reinforced with FRPs. To fill the latter gap, the current…