Optimization Method of Composite Blade Lay-up Considering Bent-Twist Coupling Effect

Abstract

In the design of composite blades, the bent-twist coupling effect can be used to reduce the aeroelastic deformation of the blades by lay-up optimization design to improve the efficiency of blade structure. In this paper, the composite blade was simplified as symmetric unbalanced cantilever laminate, and based on the classical laminated theory(CLT), two analysis parameters are proposed:the stiffness weights and load factors. The influence of the two analysis parameters on the structural deformation of the bent-twist coupling effect is studied by experiments and finite element analysis(FEA). The symmetrical laminated plates containing 0°, 90° and ±45° plies were analyzed and calculated with the feasible region of stiffness weights as the constraint condition and the minimum blade curvature as the objective function, and the optimal path of the stiffness weights relate to the load factors was obtained. A 16-plies symmetric laminated plate was used as an example to verify the optimal path of the stiffness weights. By the inverse calculation of the optimal path of the stiffness weights, the optimal ply sequences can be obtained. The method of this paper may provide some references and basis for the optimal design of the composite blades.

Keywords

• composite material
• symmetric unbalanced
• bent-twist coupling effect
• lay-up design