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Topology Optimization of a Vibrating System of Rigid and Flexible Bodies for Maximizing Repeated Eigenfrequencies

중복 고유 진동수를 갖는 진동하는 강체-유연체 계의 위상최적설계

  • Ahn, Byungseong (Dept. of Mechanical and Aerospace Engineering & IAMD, Seoul Nat'l Univ.) ;
  • Kim, Suh In (Dept. of Mechanical and Aerospace Engineering & IAMD, Seoul Nat'l Univ.) ;
  • Kim, Yoon Young (Dept. of Mechanical and Aerospace Engineering & IAMD, Seoul Nat'l Univ.)
  • 안병성 (서울대학교 기계항공공학부, 정밀기계설계공동연구소) ;
  • 김서인 (서울대학교 기계항공공학부, 정밀기계설계공동연구소) ;
  • 김윤영 (서울대학교 기계항공공학부, 정밀기계설계공동연구소)
  • Received : 2015.11.12
  • Accepted : 2016.02.29
  • Published : 2016.04.01

Abstract

When a system consisting of rigid and flexible bodies is optimized to improve its dynamic characteristics, its eigenfrequencies are typically maximized. While topology optimization formulations dealing with simultaneous design of a system of rigid and flexible bodies are available, studies on eigenvalue maximization of the system are rare. In particular, no work has solved for the case when the target frequency becomes one of the repeated eigenfrequencies. The problem involving repeated eigenfrequencies is solved in this study, and a topology optimization formulation and sensitivity analysis are presented. Further, several numerical case studies are considered to demonstrate the validity of the proposed formulation.

강체와 유연체가 혼합된 다종 구조 시스템의 동특성을 개선을 위한 최적화를 수행하는 경우, 일반적으로 그 시스템의 고유 진동수를 높이게 된다. 강체와 유연체의 시스템을 동시에 다루는 위상 최적화 정식화가 있으나, 그 시스템의 고유 진동수를 다룬 연구는 드물며, 특히 목적하는 진동수가 중복 고유 진동수 의 하나로 되는 경우를 다룬 연구는 보고된 바 없다. 본 연구에서는 중복 고유 진동수를 다루어야 하는 경우에 나타나는 수치적 문제를 해결하였으며 그 방법을 활용한 위상최적설계 정식화와 민감도 해석을 제시하였다. 그 다음, 몇 가지 수치 예제를 통해 제안된 정식화의 타당성을 검증해 보았다.

Keywords

References

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