Hybrid-Electric Aircraft Propeller Optimization

Rok Lapuh (Pipistrel)

A custom propeller was designed for a prototype Hybrid-Electric aircraft featured in the MAHEPA EU project. The optimization of the propeller was performed in three stages.

First, the propeller is designed and optimized with airfoils selected from a database. Multiple propeller properties, like twist and chord distribution, were varied to maximize take-off thrust and recuperation power, keeping climb and cruise thrust values at required values. Then, the airfoil requirements were identified and used in the airfoil optimization. It starts with a large DOE compiled from the selection of industry-standard airfoils and continues with hybrid GA-gradient optimization. At last, the optimum airfoils were then used in the propeller optimization again, to obtain the final propeller design. A 10% and 18% increase in take-off thrust was observed in the first and third stages respectively.