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An Adjoint Variable Method for Eigenproblem Design Sensitivity Analysis of Damped Systems

감쇠계 고유치문제의 설계민감도해석을 위한 보조변수법

  • 이태희 (한양대학교 기계공학부) ;
  • 이진민 (한양대학교 기계설계학과) ;
  • 유정훈 (한양대학교 기계설계학과) ;
  • 이민욱 (한양대학교 기계설계학과)
  • Published : 2005.11.01

Abstract

Three methods for design sensitivity analysis such as finite difference method(FDM), direct differentiation method(DDM) and adjoint variable method(AVM) are well known. FDM and DDM for design sensitivity analysis cost too much when the number of design variables is too large. An AVM is required to compute adjoint variables from the simultaneous linear system equation, the so-called adjoint equation. Because the adjoint equation is independent of the number of design variables, an AVM is efficient for when number of design variables is too large. In this study, AVM has been extended to the eigenproblem of damped systems whose eigenvlaues and eigenvectors are complex numbers. Moreover, this method is implemented into a commercial finite element analysis program by means of the semi-analytical method to show applicability of the developed method into practical structural problems. The proposed_method is compared with FDM and verified its accuracy for analytical and practical cases.

Keywords

Design Sensitivity Analysis;Adjoint Variable Method;Complex Eigenproblem;Damped Systems

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