Coupling bionic design and application of flow curved surface for carbon fiber composite fan blade

Carbon fiber composite fan blade (CFCFB) is gradually applied to aerospace because it possesses less density and high strength than metal materials. However, the flexural property of conventional CFCFB is generally limited due to centrifugal and aerodynamic flexural stresses. Herein, a bionic gradient double-twisted structure (BGDTS), which was composed of different modulus carbon fiber prepreg gradient structure (inspired by metopograpsus frontalis cheliped tip) and double-twisted (inspired by coelacanth scale) layup structure was designed. Besides, the flexural properties of laminates with different structures and materials were tested, and the 3D Hashin failure criterion was used for simulation analysis. The experimental and simulation results showed that bionic gradient double-twisted structure laminate (BGDTSL) had the best flexural performance (peak flexural force 1125.12 N). Then, the excellent molding accuracy of CFCFB was verified by the three-dimensional scanning test (molding accuracy less than 0.56 mm). Among, the tip, middle, and root peak flexural force of the BGDTS-CFCFB were 7022 N, 3327 N, and 5184 N, which increased by 9.27%, 4.59%, and 14.31% compared with traditional structure CFCFB prepared by T800 (TS-CFCFB@T800). The researches in this work offer a prospective way to effectually devise and manufacture exquisitely structured CFCFBs that are more suitable for aeronautical engineering.