AME Seminar: Adrien Bouskela
Thursday, April 25, 2024 at 4:00 p.m.
Adrien Bouskela
PhD Student
Aerospace and Mechanical Engineering
University of Arizona
"Theoretical Modeling and Flight Experiments of Sailplane Dynamics in Non-uniform Winds"
AME Lecture Hall, Room S212 | Zoom Link
Abstract: Long endurance flight is challenged by the limited energy resources carried on-board fixed-wing aircraft, particularly in unmanned aerial vehicles. Nature provides an elegant solution in the form of birds, such as Albatross, which have been observed traveling long distances at minimal energy cost. Previous studies utilized three and six degree of freedom models for flight dynamics of sailplanes in the form of optimization problems for a few wind profiles. The results have informed design criteria; however, our review of existing literature highlights an ongoing deficiency in comprehending the dynamics between the atmosphere and sailplanes across fundamental flight paths.
Significant energy gains can be achieved from dynamic effects when flights are conducted in the unsteady flows of atmospheric boundary layers, orographic winds, high-altitude jet streams and associated shear layers. Our incremental analysis of the sailplane subjected to a gust showed that the resulting lift force produces a non-zero projection in the direction of motion. The present work theoretically studies dynamic effects in non-uniform winds for canonical flight trajectories such as: orbits, ascending and descending straight flights, upward and downward spirals and pull-ups. Numerical solutions for a circular flight path inclined to the horizontal verified experimental results which showed significant increases in kinetic energy up to the transonic regime. Through pullout spiraling, this accumulated kinetic energy can be further transformed into potential energy. Simulations of various flight maneuvers extended to Mars's atmosphere have demonstrated the feasibility of long-endurance flights based on available data of its planetary atmosphere. Established similarity with flight in Earth’s stratosphere showed it was a valid candidate for experimentation and design validation.
Autonomous controls were implemented in flight experiments on three-meter wingspan class sailplanes at low and high altitude. Flight data match trends obtained in theoretical analyses and showed that sustained flight is possible from the combined vertical and horizontal unsteady winds.
Bio: Adrien Bouskela is a PhD candidate at the University of Arizona's Aerospace and Mechanical Engineering Department. He is originally from France, where he graduated with a master’s in aerospace systems engineering before joining the University of Arizona in 2017 to pursue his interests in aircraft and spacecraft flight dynamics and mission concepts. He is looking forward to completing his doctorate, with research including numerical and experimental studies for Earth and Mars glider dynamics and pursuing a career in the associated field.