Optimization Design of Fiber-Reinforced Composite Fan Blade with Hollow Structure

Fiber-reinforced composite fan blades, especially hollow fan blades, are gradually applied to civil aero engines, due to their light weight and good vibration damping performance. In this paper, the research on the optimization design method of lay-up angle and hollow structure of fiber-reinforced composite is carried out. Firstly, a modified Tsai-Wu failure criterion considering interlaminar performance was established and validated based on laminate tests. Secondly, the grey relational analysis method is combined with entropy-based weight assignment method to achieve the optimal lay-up angles. This method can visually present the influence degree layer angle of pavement on the quality, strength, vibration, stiffness, and other performance indicators of fan blade. The number of tests required is small and has strong engineering applicability. Then, the parametric modeling method of the hollow structure is developed, and genetic algorithm is combined to achieve optimal design of the hollow structure size. Finally, the two-step optimization iteration of lay-up angles and hollow structure determines the lightweight and high-performance fiber-reinforced composite fan blades. The weight of the hollow fan blade is reduced by 37.0% compared with the initial structure while satisfying the mechanical properties of the blade, which proves the feasibility of the design method and provides technical support for the design of the actual fan blade.