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numerical difficulties associated with using equality constraints to achieve multi-level decomposition in structural optimizationThere has been recent interest in multidisciplinary multilevel optimization applied to large engineering systems. The usual approach is to divide the system into a hierarchy of subsystems with ever increasing detail in the analysis focus. Equality constraints are usually placed on various design quantities at every successive level to ensure consistency between levels. In many previous applications these equality constraints were eliminated by reducing the number of design variables. In complex systems this may not be possible and these equality constraints may have to be retained in the optimization process. In this paper the impact of such a retention is examined for a simple portal frame problem. It is shown that the equality constraints introduce numerical difficulties, and that the numerical solution becomes very sensitive to optimization parameters for a wide range of optimization algorithms.
Document ID
19860054067
Document Type
Conference Paper
Authors
Thareja, R.
(Virginia Polytechnic Inst. and State Univ. Blacksburg, VA, United States)
Haftka, R. T.
(Virginia Polytechnic Institute and State University Blacksburg, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1986
Subject Category
STRUCTURAL MECHANICS
Report/Patent Number
AIAA PAPER 86-0854
Funding Number(s)
CONTRACT_GRANT: NAG1-168
Distribution Limits
Public
Copyright
Other