Simulação numérica via método dos elementos finitos de stent-graft de nitinol

Abstract

The present work provides a numerical model of an "endovascular Graft". Endovascular grafts are the main devices used in the treatment of aneurysms in a non-invasive manner. However, few studies have been developed seeking an evaluating methodology. A Finite Element Method (FEM) analysis is developed to assess the interaction between the Stent-Graft (SG) and the aortic wall. This method is chosen due to the possibility of that analysis and because it evaluates the e!ectiveness of the device. A literature research is made to correctly characterize the properties of the commercial material of such stent, as well as the mechanical behavior of both, SG and aorta. In the same way, the finite element types and mesh parameters are appropriately selected to the model, in order to obtain accurate results. For this development, the main challenge is to properly select the boundary conditions of the assembly, SG and aorta. A radial displacement is applied aiming to obtain equivalent stress results. At last, a convergence analysis is made, followed by a qualitative and quantitative comparison of the stress distribution based on the literature, to finally validate the methodology.