A Novel Composite Design Optimization Method for Minimized Manufacturing Cost with Improved Performances

The design optimization of composite structures generally takes the lightest structural weight or the best performance index as the goal. With the advancement of the aerospace industry and increasingly fierce market competition, the manufacturing cost has become an essential factor affecting the market competitiveness of aircraft and the expansion of composite applications. This study uses a manufacturing process cost model based on process flow simulation to establish objective functions, uses MSC.Patran/Nastran to analyze static strength and aeroelasticity and establish performance constraints. The optimization program is constructed on the Isight software platform based on the Bliss step-by-step idea and multi-island genetic algorithm. The design optimization method of composite structure targeting at manufacturing cost is thus established. On a composite wing with three typical fabrication routes, the manufacturing cost is reduced by 20.23%, 28.18%, and 37.11%. Utilizing the structural characteristics of the objective function and through the control of variables, the optimization simultaneously realized structural weight reduction and performance improvements, achieving reductions up to 18.09% in structural weight, 7.03% in wingtip displacement, 43.65% in torsion angle, and enhancements up to 14.63% in flutter speed.