Design of a Quiet Propeller for an Electric Mini Unmanned Air Vehicle

Designing a quiet and efficient propeller is a demanding task because these two goals often lead to contradictory design trends. The task becomes even more complicated when additional constraints are introduced. This paper presents a multidisciplinary design optimization process for designing a quiet propeller under various constraints. The acoustic model of the propeller is presented in detail, including its validation. The new process is used to design a quiet propeller for an electric mini unmanned air vehicle. This design is subjected to power, structural, and side constraints. The design variables include blade geometry, blade cone angle, propeller radius, number of blades, and rotational speed. It is shown that the motor characteristics have an important influence on the optimization, and it is therefore important to take them into account during the design process. The influences of the various parameters on the design and propeller's characteristics are presented and discussed in detail.