AEROELASTIC ANALYSIS OF FLEXIBLE WINGS WITH DISTRIBUTED ELECTRIC PROPULSION

The emergence of electric-powered aviation is leading to innovative aircraft configurations that incorporate slender, high-aspect-ratio wings with distributed propulsion systems. While these designs offer substantial benefits in efficiency and emissions reduction, they present significant aeroelastic challenges. Notably, thinner and more flexible wings are increasingly prone to wing flutter, and the flexible mounting of propellers on these wings introduces a susceptibility to whirl flutter-a dynamic instability driven by gyroscopic forces as propeller hubs undergoes a precessional motion around the stationary thrust axis. This research aims to explore the interaction between wing motion and whirl flutter in flexibly attached propellers on elastic wings, as well as the impact of propeller dynamics on wing flutter characteristics. To achieve this, first, the aerodynamic derivatives of a constant pitch propeller under windmilling conditions were determined using Houbolt-Reed theory. Subsequently, a classical whirl flutter analysis was performed for an isolated propeller model, based on Bennet and Bland's approach. Following the validation of the propeller whirl model, a coupled flexible wing-propeller model was developed. The wing's structural behavior was represented using Euler-Bernoulli beam theory, and the system's classical binary flutter was analyzed through Theodorsen's unsteady aerodynamic theory.