An adjoint variable method for structural design sensitivity analysis of a distinct eigenvalue problem

A design sensitivity analysis of high frequency structural-acoustic problem is formulated and presented. The Energy Finite Element Method (EFEM) is used to predict the structural-acoustic responses in high frequency range, where the coupling between the structural and acoustic domain are modeled by using radiation efficiency. The continuum design sensitivity formulation is derived from the governing equation of EFEM and the discrete method is applied in the variation of the structural-acoustic coupling matrix. The direct differentiation and adjoint variable method are both developed for the sensitivity analysis, where the difficulty of the adjoint variable method is overcome by solving a transposed system equation. Parametric design variables such as panel thickness and material damping are considered for sensitivity analysis, and the numerical sensitivity results show excellent agreement comparing with the finite difference results.

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A Sequential Adjoint Variable Method in Design Sensitivity Analysis of NVH Problems

10.1115/imece2001/nca-23511 ◽

2001 ◽

Author(s):

N. H. Kim ◽

K. K. Choi ◽

J. Dong ◽

C. Pierre ◽

N. Vlahopoulos ◽

...

Keyword(s):

Sensitivity Analysis ◽

Boundary Element ◽

Design Sensitivity ◽

Variable Method ◽

Design Sensitivity Analysis ◽

Response Analysis ◽

Adjoint Variable Method ◽

Adjoint Variable ◽

Structural Dynamic ◽

Structural Part

Abstract A design sensitivity analysis of a sequential structural-acoustic problem is presented. A frequency response analysis is used to obtain the dynamic behavior of an automotive structure, while the boundary element method is used to solve the pressure response of an interior, acoustic domain. For the purposes of design sensitivity analysis, a direct differentiation method and an adjoint variable method are presented. In the adjoint variable method, an adjoint load is obtained from the acoustic boundary element re-analysis, while the adjoint solution is calculated from the structural dynamic re-analysis. The evaluation of pressure sensitivity only involves a numerical integration process for the structural part. The proposed sensitivity results are compared to finite difference sensitivity results with excellent agreement.

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Design sensitivity analysis for transient eddy current problems using finite element discretization and adjoint variable method

IEEE Transactions on Magnetics ◽

10.1109/20.497469 ◽

1996 ◽

Vol 32 (3) ◽

pp. 1242-1245 ◽

Cited By ~ 24

Author(s):

Il-Han Park ◽

In-Gu Kwak ◽

Hyang-Beom Lee ◽

Song-Yop Hahn ◽

Ki-Sik Lee

Keyword(s):

Sensitivity Analysis ◽

Finite Element ◽

Eddy Current ◽

Design Sensitivity ◽

Variable Method ◽

Transient Eddy ◽

Adjoint Variable Method ◽

Adjoint Variable ◽

Finite Element Discretization ◽

Element Discretization

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Second-Order Design Sensitivity Analysis of Mechanical System Dynamics by a Mixed Direct Differentiation Adjoint Variable Method

Volume 2: 24th Design Automation Conference ◽

10.1115/detc98/dac-5575 ◽

1998 ◽

Author(s):

Javier Urruzola ◽

José Manuel Jiménez

Keyword(s):

Sensitivity Analysis ◽

Design Sensitivity ◽

Second Order ◽

Variable Method ◽

Adjoint Variable Method ◽

Adjoint Variable ◽

Direct Differentiation ◽

Design Variables ◽

Adjoint Variables ◽

Derivatives Of

Abstract This paper presents a new approach to second order sensitivity analysis of multibody dynamics. Adjoint variables together with direct differentiation are used to derive first- and second-order derivatives of measures of dynamic response with respect to design variables. It is shown that the proposed method can be compared advantageously to the fully adjoint variable method proposed by Haug in terms of simplicity and numerical cost. In order to validate the algorithm, a simple oscillator example proposed by Haug is solved analytically and by the mixed method, with identical results.

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