Evaluation of Aeroelastic Models for Gust Response Prediction in Very Flexible Wings

ifasd2024 Tracking Number 35

This paper compares aeroelastic models for gust response prediction in very flexible wings. The investigations focus on the Pazy wing benchmark developed at Delft University of Technology for gust response experiments in low-speed flow. The comparisons consider two geometrically nonlinear aeroelastic models of the wing, which comprise an equivalent beam representation of the structure coupled with unsteady potential flow aerodynamics based on either strip theory with wingtip corrections or the vortex-lattice method. The study examines wing responses to 1-cosine vertical gust inputs for various maximum gust velocities, flow speeds, and root angles of attack, exciting a wide range of deflections. The aeroelastic models based on corrected strip theory and the unsteady vortex-lattice method predict maximum wing tip vertical displacements that differ by less than 3%. The models also agree on the characteristic frequency and phase during the free decay after the gust. However, the model based on strip theory predicts a faster free decay due to higher aerodynamic damping, consistent with findings from previous flutter investigations focused on the Technion Pazy wing. These results provide new insights into the impact of model complexity on aeroelastic prediction accuracy for very flexible wings, expanding the scope of previous studies to encompass gust responses.