Topology optimization of periodic barriers for surface waves
- PDF / 3,529,867 Bytes
- 16 Pages / 595.276 x 790.866 pts Page_size
- 92 Downloads / 172 Views
INDUSTRIAL APPLICATION PAPER
Topology optimization of periodic barriers for surface waves Ze Liu 1 & Hao-Wen Dong 2,3,4 & Gui-Lan Yu 1 Received: 13 March 2020 / Revised: 18 July 2020 / Accepted: 23 July 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Dispersion engineering is always the important topic in the field of artificial periodic structures. In particular, topology optimization of composite structures with expected bandgaps plays a key role. However, most reported studies focused on topology optimization for bulk waves, and the optimization for surface wave bandgaps (SWBGs) is still missing. In this paper, we develop a topology optimization framework based on the genetic algorithm and finite element method to design periodic barriers embedded in semi-infinite space for reducing surface waves on demand. The objective functions for SWBGs are proposed based on the energy distribution properties of surface waves. The numerical results show that the optimization framework has stable convergence for this problem and is effective to optimize SWBGs. Considering large SWBGs and low filling fraction of solids, we investigate single- and multi-objective optimizations, respectively, and obtain novel wave barriers with good performance. The beneficial configuration features and mechanism of broadband SWBGs from the optimized results are explored. The results indicate that for the first-order SWBG, most optimized structures consist of a main scatterer at the center and some subsidiary scatterers near the surface. The rigid body resonance of the main scatterer determines the lower edge of SWBG, and the subsidiary scatterers can regulate the upper edge. Higher-order SWBGs are generated from the interaction of multiple scatterers, whose relative distance has a great influence on the position of SWBGs. The optimized structures can make the surface waves propagate far away from the surface within the frequencies of bandgaps, leading to a strong attenuation of surface vibration. In practice, our topological optimization framework is promising in designing high-performance surface wave devices and novel isolating structures for earthquake or environmental vibration in civil engineering. Keywords Topology optimization . Periodic barriers . Surface wave . Bandgap . Multi-objective optimization
1 Introduction During the past two decades, the artificial periodic structures, a kind of composite structure with periodically distributed
Responsible Editor: Seonho Cho * Hao-Wen Dong [email protected] * Gui-Lan Yu [email protected] 1
School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, People’s Republic of China
2
Department of Mechanics, School of Mechanical Engineering, Tianjin University, Tianjin 300350, People’s Republic of China
3
Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong, People’s Republic of China
4
Department of Applied Mechanics, University of Science and Technology Beijing, Beijing 100083, People’s Republic of China
mater
Data Loading...
