The University of Southampton
University of Southampton Institutional Repository

Approximations and reanalysis over a parameter interval for dynamic design

Approximations and reanalysis over a parameter interval for dynamic design
Approximations and reanalysis over a parameter interval for dynamic design
In many design search and optimization situations, the objective of optimization or design improvement is closely related to one or more natural frequencies of a dynamic system. The problem typically involves solving an eigenvalue problem repeatedly for a large set of values of the parameters which describe the system or the structure being designed. When the system is complex, the parameter space tends to be large (i.e, the number of parameters that define the geometry, material properties, etc is large). The situation is further complicated by the fact that complex geometries usually require a large number of degrees of freedom for a reasonably accurate analysis (e.g. an ap9propriate finite-element analysis). For this reason, the design search and optimization problem tends to be computationally very demanding. In most situations, it is this step involving the solution of the eigenproblem associated with the free vibration that consumes most computational resources.
The present note is motivated by this engineering need. A method based on interpolation for an approximate estimation of eigenvalues is presented. Instead of the usual approximation around a reference design, the approach here is to find approximations (at possibly several points) over an interval of the parameter of interest. This problem has been attempted via an alternative route by Bhaskar (1) where the approximations are sought for eigenvectors by interpolating the mode shapes themselves over the parameter interval of interest; trial vectors obtained in this manner were used in a Rayleigh-quotient approximation. The present scheme differs in that it provides approximations for eigenvalues directly form the estimates that use exact eigensolutions at the terminal points of the design interval.
0022-460X
178-186
Bhaskar, A.
d4122e7c-5bf3-415f-9846-5b0fed645f3e
Sahu, S.S.
65fc8f9f-60e2-4f56-988d-a2d3b0302a6b
Nakra, B.C.
90485b74-82cc-4f32-a7d3-c49135d1a74d
Bhaskar, A.
d4122e7c-5bf3-415f-9846-5b0fed645f3e
Sahu, S.S.
65fc8f9f-60e2-4f56-988d-a2d3b0302a6b
Nakra, B.C.
90485b74-82cc-4f32-a7d3-c49135d1a74d

Bhaskar, A., Sahu, S.S. and Nakra, B.C. (2001) Approximations and reanalysis over a parameter interval for dynamic design. Journal of Sound and Vibration, 248 (1), 178-186. (doi:10.1006/jsvi.2001.3686).

Record type: Article

Abstract

In many design search and optimization situations, the objective of optimization or design improvement is closely related to one or more natural frequencies of a dynamic system. The problem typically involves solving an eigenvalue problem repeatedly for a large set of values of the parameters which describe the system or the structure being designed. When the system is complex, the parameter space tends to be large (i.e, the number of parameters that define the geometry, material properties, etc is large). The situation is further complicated by the fact that complex geometries usually require a large number of degrees of freedom for a reasonably accurate analysis (e.g. an ap9propriate finite-element analysis). For this reason, the design search and optimization problem tends to be computationally very demanding. In most situations, it is this step involving the solution of the eigenproblem associated with the free vibration that consumes most computational resources.
The present note is motivated by this engineering need. A method based on interpolation for an approximate estimation of eigenvalues is presented. Instead of the usual approximation around a reference design, the approach here is to find approximations (at possibly several points) over an interval of the parameter of interest. This problem has been attempted via an alternative route by Bhaskar (1) where the approximations are sought for eigenvectors by interpolating the mode shapes themselves over the parameter interval of interest; trial vectors obtained in this manner were used in a Rayleigh-quotient approximation. The present scheme differs in that it provides approximations for eigenvalues directly form the estimates that use exact eigensolutions at the terminal points of the design interval.

Text
bhas_01a.pdf - Accepted Manuscript
Download (1MB)

More information

Published date: 2001

Identifiers

Local EPrints ID: 21834
URI: http://eprints.soton.ac.uk/id/eprint/21834
ISSN: 0022-460X
PURE UUID: 6c21e0d7-7b7c-4563-94d8-b76600f79ec4

Catalogue record

Date deposited: 15 Mar 2006
Last modified: 15 Mar 2024 06:32

Export record

Altmetrics

Contributors

Author: A. Bhaskar
Author: S.S. Sahu
Author: B.C. Nakra

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×