Effects of bend-twist coupling on composite propeller performance

An investigation of a conventional propeller, made from composite materials, was conducted in which propeller characteristics were studied under quasi-static aerodynamic loading. Emphasis was placed on understanding the effects of bend-twist coupling of composite laminates on propeller performance. The classical blade element theory of propellers was used to calculate propeller characteristics and the aerodynamic force distribution acting on the propeller. The finite-element method was used to calculate the resulting deformation of the propeller blades. A simple algorithm was used in which propeller blade deformation and resulting changes in loading conditions were calculated repeatedly until equilibrium between deformation and loading was achieved. Results show that improvements in propeller performance are possible using the bend-twist coupling of composite laminates. Additionally, this study shows that the numerical approach developed by the authors is well suited for analyzing the performance characteristics of composite propellers.