Title| Isogeometric Analysis in Structural Mechanics
Speaker| Associate Professor Josef Kiendl, Norwegian University of Science and Technology, Trondheim, Norway.
Date| 5 July 2017 5 July 2017 (Wednesday)
Time| 1400 – 1500
Venue| Think Tank 19, Building 2, Level 3 (2.304)
Isogeometric analysis is a novel method of computational analysis where functions used to describe geometries in Computer Aided Design (CAD) are adopted as basis for analysis. Due to this unified geometric representation, the model transfer from design to analysis, called mesh generation, is omitted providing a better integration of design and analysis. NURBS are the most widespread technology in today’s CAD modeling tools and therefore are adopted as basis functions for analysis. Apart from the geometrical advantages, NURBS-based isogeometric analysis has proven superior approximation properties compared to standard finite element analysis for many different applications. Furthermore, the high continuity between elements also allows the discretization of higher order PDEs, which is especially useful in structural mechanics, where the classical plate and shell theories, based on Kirchhoff’s kinematic assumption, can be implemented in a straightforward way.
We show an isogeometric shell analysis framework with formulations ranging from linear, geometrically nonlinear, and fully nonlinear shell models. All formulations are based on the Kirchhoff-Love shell theory and are rotation-free, i.e., using only displacement degrees of freedom. These formulations are then employed for the simulation of various problems of nonlinear structural mechanics, including large deformations and large strains, buckling, hyperelastic and elastoplastic materials, as well as brittle fracture. Furthermore, we show that this framework allows for the effective integration of analysis into CAD design software, its extension to isogeometric shape optimization, and the application to fluid-structure-interaction problems including the simulation of offshore wind turbine blades and bioprosthetic heart valves.
ABOUT THE SPEAKER
Josef Kiendl is an “Onsager fellowship” Associate Professor at the Department of Marine Technology of the Norwegian University of Science and Technology, NTNU. He received his Master’s and PhD degrees in Civil Engineering at the Technical University of Munich, Germany. After his PhD, he worked as a post-doctoral researcher in the group of Computational Mechanics and Advanced Materials at the University of Pavia, Italy, and as Assistant Professor for Computational Mechanics at the Technical University of Braunschweig, Germany. His main research interests lie in developing efficient isogeometric methods for nonlinear structural mechanics for the simulation of complex problems including large deformations, nonlinear material response, fracture, fluid-structure-interaction, and in the integration of isogeometric design, analysis, and shape optimization.