Multi-directional cloaking structure design using topology optimization

Abstract

Cloaking structure designs have been widely performed in a form of metamaterial development. However, physics-based design approach makes it difficult to define complex material profiles. This study proposes an alternative design method for multi-directional cloak design via topology optimization method using a dielectric material. The phase field design method, which uses the reaction-diffusion equations combined with the double well potentials as the update scheme for design variables, is employed for systematic derivation of a topological configuration of the cloaking structure. In addition, the concept of symmetric design sensitivity mapping is introduced for multi-directional cloaking effect. Design results of four-, six- and eight-directional cloak are presented, and experimental verification was performed for six-directional cloak using the fabricated structure through 3D printing technology.

KEYWORDS:

• Multi-directional cloak
• topology optimization
• phase field design method
• dielectric material
• experimental verification

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MEST) [NRF-2019R1A2B5B01069788] and the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Ministry of Trade, Industry and Energy, Republic of Korea [No. 20204030200010].

Notes on contributors

Mingook Jung

Mingook Jung is studying for Ph.D. degree at Mechanical Engineering Department, Yonsei University, Seoul, Korea.

Namjoon Heo

Namjoon Heo got his Ph.D. degree at Mechanical Engineering Department, Yonsei University. He is working at the SK innovation Institute of Technology Innovation, Daejeon, Korea.

Jinwoo Park

Jinwoo Park got his Ph.D. degree at Hanyang University, Seoul, Korea. He is working at Agency for Defense Development, Daejeon, Korea.

Jeonghoon Yoo

Jeonghoon Yoo got his Ph.D. degree at University of Michigan, Ann Arbor, USA. He is working at Mechanical Engineering Department, Yonsei University, as a professor.