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Exact strip analysis and optimum design of aerospace structures

Published online by Cambridge University Press:  03 February 2016

D. Kennedy  and
C. A. Featherston
D. Kennedy
Affiliation:
[email protected]
C. A. Featherston
Affiliation:
Cardiff University, Cardiff School of Engineering, Cardiff, UK
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Abstract

Minimisation of airframe mass reduces the costs of materials and manufacturing, as well as fuel consumption and atmospheric emissions. Fast, reliable analysis tools are required during preliminary design, when many alternative configurations and load cases are considered. The modelling and computational costs of finite element analysis are avoided by employing exact strip solutions of the governing differential equations, using the Wittrick-Williams algorithm to solve the resulting transcendental eigenproblems of buckling and vibration. This paper reviews recent enhancements to the exact strip method for analysis and optimum design of aerospace structures, using the specialist software VICONOPT. Lighter composite panels can be designed by obtaining reliable estimates of the reduced postbuckling stiffnesses when loaded in compression and shear. Further advances include discrete optimisation of layer thicknesses to allow for practical composite manufacturing constraints, vibration constraints, and a newly extended multi-level interface combining finite element analysis of a whole wing with exact strip postbuckling design of individual panels.

Type
Research Article
Information
The Aeronautical Journal , Volume 114 , Issue 1158 , August 2010 , pp. 505 - 512
Copyright
Copyright © Royal Aeronautical Society 2010 

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