Design of a Variable Pitch, Energy-Harvesting Propeller for In-Flight Power Recuperation on Electric Aircraft

In this thesis project, it is investigated to what extent the energy consumption of an electric aircraft can be improved by using a variable pitch and RPM propeller, including energy recuperation during the descent, with respect to a constant pitch propeller. The largest percentage of total mission energy saved using the variable pitch propeller with respect to the constant pitch propeller is about 4.1% for a cruise distance of 5 km when using two blades and about 3.0% for three blades. This percentage reduces to approximately 0.7%, both for two and three blades, when the cruise distance is 200 km. A two-bladed propeller therefore turns out to be the best option. Regarding the effect of the propeller airfoil camber and thickness with respect to the NACA 4415 airfoil, the NACA 0015 airfoil performs best on a short range mission and the NACA 2415 performs best on a long range mission.Aerospace Engineering | Aerodynamics and Wind Energ