Aeroelastic Design of Propellers with Optimized Load-Distribution Characteristics

The mathematical model and experimental verification of deformable propeller blades are presented in this paper. The propeller aerodynamics model is based on an extended bladeelement momentum model while the Euler-Bernoulli beam theory and Saint-Venant theory of torsion are used to account for bending and torsional deformations of the blades, respectively. The proposed blade-element momentum model extends the standard bladeelement momentum theory with the aim of providing a quick and robust model of propeller action capable of treating high aspect-ratio propeller blades with a blade axis of arbitrary geometry. Based on the proposed mathematical model a propeller blade aeroelastic design procedure and its associated analysis algorithm are established. Experimental validation was carried out with an objective of evaluating the performance of the developed mathematical model and the design strategy. Both theoretical and experimental results are presented along with pertinent concluding remarks.

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