Abstract:

A minimum weight design procedure of wing structures with composite skins is described briefly, in which strength, frequency, displacement, divergence velocity, control surface efficiency, flutter speed and thickness are considered as constraints. Main methods used in the procedure are also presented. New engineering requirements are imposed upon the integrated optimization design of composite structures. Corresponding methods to meet these requirements are suggested and implemented in a newly developed Composite Structure Analysis and Optimum Design Program System . By using the automated design tool, the integrated optimization design for a delta wing structure with composite skins was performed. Under the constraints of unidirectional strains, total thickness limit, balanced symmetrical limit and flutter speed, the optimum thickness of each ply orientation has been obtained. From the full scale tests of the wing for strength, durability and damage tolerance, and from the tests of ground resonance oscillation and flight of the airplane, it is indicated that tests values are in good compliance with the optimization design results and the integrated optimum design procedure and methods described in this paper can be used for the practical optimization design of wing structures with composite skins.

Key words: optimum, structure design, composite skins