Paper number 840

COMPUTER-AIDED LAMINATE SELECTION USING A GRAPHICAL METHOD

P.M.Weaver

Department of Aerospace Engineering, University of Bristol, Queens Building, University Walk, Bristol, BS8 1TR,UK
E-mail: paul.weaver@bristol.ac.uk

Summary

This paper introduces a methodology for selection of laminates. Software that implements these ideas is also presented. Optimisation of laminate fibre angles is difficult for multiple load cases and objectives-there are many local minima to assess. An alternative approach is presented here that circumvents the need for conventional optimisation strategies that often prove difficult and complicated to implement. The basic idea is to build a database that stores appropriate properties of all permutations of lay-up angles for a laminate. Rather than access these properties by a question and answer, black-box technique, a graphical method is introduced. The designer can select viable laminates by first plotting a succession of 2-D charts containing relevant properties. Then, using simple on-screen techniques, the number of potential laminates is visually reduced by selecting those with desirable properties. The optimisation of a cylindrical shell, subject to axial compression, that undergoes simultaneous Euler-type buckling and local buckling is examined.

Keywords

design, optimisation, carpet plot, lay-up selection, local buckling, global buckling, cylindrical shell, selection.