Speaker: Adnan Kefal, Istanbul Technical University
Title: Large-Scale Design, Analysis, and Optimization: Where Engineering Challenges and Computational Mechanics Meet
Date/Time: September 25, 2019 / 13.40-14.30
Place: FENS G032
Abstract: Aircraft/ship/submarine structural design demands the design of large structures made of large numbers of tensile, bending, and buckling resistant components. Additionally, as technology progresses, the need for cost-effective, lightweight, and high-performance structures have significantly increased. Therefore, a strong interaction between design, analysis, and manufacturing should be taken into account through utilizing optimization techniques during the design of large structures. For this purpose, optimization techniques and structural topology estimation have been unified for a long time now. Topology optimization finds an optimal distribution of material deposition within a predefined design domain whilst improving an objective function (e.g., stiffness) and satisfying design constraints. In literature, finite element method is commonly used with topology optimization algorithms to determine optimum topology of load bearing structures. However, it may possess various difficulties and limitations for handling the problems with moving boundaries, large deformations, and cracks/damages. To remove limitations of the mesh-based topology optimization, this seminar presents a robust and accurate approach based on the innovative coupling of Peridynamics (PD) (a meshless approach) and topology optimization (TO), abbreviated as PD-TO. The main advantage of the PD-TO methodology is its ability to handle topology optimization problems of cracked structures without requiring complex treatments for mesh connectivity. To present the capability, efficiency, and accuracy of the PD-TO approach, various challenging two- and three-dimensional large-scale optimization problems with and without defects (cracks) are solved under different boundary conditions. Applications also include multi-material topology optimization and print-ready designs for additive manufacturing. In addition to the PD-TO approach, the seminar briefly covers dynamic analysis of functionally graded materials, computational modelling for toughness enhancement, structural health monitoring, energy harvesting, and isogeometric analysis of composite structures.
BIO: Dr. Adnan Kefal is an Assistant Professor and the Vice Dean of Research & Development at the Faculty of Naval Architecture and Ocean Engineering, Istanbul Technical University (ITU). He completed his undergraduate education in 2013 with the first rank in the same faculty at ITU. He received his Ph.D. degree in 2017 from Naval Architecture, Marine and Ocean Engineering Department at the University of Strathclyde, Glasgow, UK in the fields of computational structural mechanics and structural health monitoring. During his PhD studies, he worked as a visiting researcher at NASA Langley Research Center, USA in summer 2016. Prior to joining ITU, he was a research scientist at the Integrated Manufacturing Technologies Research and Application Center of Sabanci University. Dr. Kefal’s areas of expertise involve computational mechanics and engineering optimization techniques with the focus on large-scale structures, topology optimization, structural health monitoring, shape and stress sensing, energy harvesting, and mechanics of composite structures. He is co-author of more than 13 journal articles published in SCI-indexed high impact journals, and also prepared and presented over 22 conference papers on these topics.
Contact: Emre Erdem