Optimization of Propeller Based Propulsion System

TLDR

Propeller design requires integrating aerodynamics, structural analysis, and acoustics. The study presents a new MDO-based method for optimal propeller design. The method integrates multiple analysis tools with an optimization engine, employing three optimization schemes to generate optimal and alternative propeller designs for an ultralight aircraft. Compared to the Betz-based classical design, the MDO approach yields superior propeller performance and highlights the need to consider the entire air‑vehicle and propulsion system rather than the propeller alone.

Abstract

Propeller design is a complex task that involves a variety of disciplines such as: aerodynamics, structural analysis, and acoustics. A new method of designing an optimal propeller which is based on a MDO (Multidisciplinary Design Optimization) approach is presented. By combining various analysis tools with an optimization tool, a powerful and flexible design method is obtained. During the design process three different optimization schemes are used, leading the design to its optimal goal. This new method is applied for the design of a propeller for an Ultralight aircraft. Several optional designs for different design goals are presented. The results of the new method are compared with results of the classical design method, based on Betz's condition, which considers only the aerodynamic performance of the propeller. The importance of addressing the characteristics of the entire air-vehicle, its aerodynamic characteristics and its propulsion system (engine, gear box, etc.), rather than only the isolated propeller, is emphasized.