Search results for " Finite Element"
showing 5 items of 145 documents
Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEM) of a Customized Stent-Graft for Endovascular (EVAR) Treatment of Abdominal Aorti…
2023
Background: The treatment of abdominal aortic aneurysm (AAA) is today commonly treated by inserting a stent-graft by the endovascular route, without resorting to open surgery. However, some clinical cases do not allow this less invasive approach, meaning that the stent-graft cannot be inserted and open surgery is used. Methods: In the study, we propose a fluid–structure interaction (FSI) analysis of an aneurysmatic aorta that could not be treated with Endovascular Aneurysm Repair (EVAR). The vessel is reconstructed through segmentation from CT scans and subsequently modeled on CAD software to create the surface and thickness of the vessel itself. Subsequently, we proceeded to carry out Comp…
Residual a posteriori error estimation for frictional contact with Nitsche method
2023
We consider frictional contact problems in small strain elasticity discretized with finite elements and Nitsche method. Both bilateral and unilateral contact problems are taken into account, as well as both Tresca and Coulomb models for the friction. We derive residual a posteriori error estimates for each friction model, following [Chouly et al, IMA J. Numer. Anal. (38) 2018, pp. 921-954]. For the incomplete variant of Nitsche, we prove an upper bound for the dual norm of the residual, for Tresca and Coulomb friction, without any extra regularity and without a saturation assumption. Numerical experiments allow to assess the accuracy of the estimates and their interest for adaptive meshing …
Experimental Observation of a Large Low-Frequency Band Gap in a Polymer Waveguide
2018
The quest for large and low-frequency band gaps is one of the principal objectives pursued in a number of engineering applications, ranging from noise absorption to vibration control, and to seismic wave abatement. For this purpose, a plethora of complex architectures (including multiphase materials) and multiphysics approaches have been proposed in the past, often involving difficulties in their practical realization. To address the issue of proposing a material design that enables large band gaps using a simple configuration, in this study we propose an easy-to-manufacture design able to open large, low-frequency complete Lamb band gaps exploiting a suitable arrangement of masses and stif…