Doctorat design of High-Altitude Platform Station (HAPS) drones

Framework

This project focuses on the design of High-Altitude Platform Station (HAPS) drones. These solar-powered drones act as pseudo-satellites, providing enhanced surveillance capabilities while reducing logistical costs. Due to their large wingspan (approximately 50 meters) and highly flexible structure, these drones are particularly susceptible to aeroelastic instabilities, such as wing flutter, which may or may not be coupled with aircraft motion. Controlling the flutter of highly flexible wings in HAPS drones is currently a major challenge that limits their operational flight envelope. Furthermore, in flying-wing configurations, a coupling between the wing’s flexible modes and the aircraft’s rigid-body modes reduces the critical flutter speed.

This thesis, titled "Nonlinear Aeroelastic Modeling of a Highly Flexible Wing for HALE Drones", will be conducted as part of the French national research project FlexHALE, "Prediction and Prevention of Aeroelastic Risks for Highly Flexible HALE Pseudo-Satellites".

Missions

The objective of this PhD research is to improve predictive models for the dynamics of a highly flexible flying wing under aeroelastic flutter conditions. The study will focus on integrating flight dynamics into an existing aero-structural code, incorporating nonlinear aerodynamic phenomena (such as dynamic stall), and developing more efficient numerical simulation approaches. The ultimate goal is to provide fast and accurate simulations of post-flutter dynamics to optimize the composite wing structure for better aeroelastic control.

This research spans multiple disciplines, including structural vibrations, aerodynamics, numerical methods, and applied mathematics. While no experimental work is planned within the PhD itself, other team members (two additional PhD students) will handle those aspects. The project is conducted in collaboration with ISAE-Supméca, INRIA, and Sorbonne University. The second phase of the PhD will focus more on numerical methods for optimization techniques and will be carried out in direct partnership with INRIA.

The Air and Space Academy is a major military school (with EPSCP-GE status) located in Salon-de- Provence, authorized to deliver the title of engineer. It is a member of the Conférence des Grandes Écoles and the ISAE group (SUPAERO, ENSMA, ESTACA, The Air and Space Academy). It is responsible for the initial training of all Air Force and Space Force officers.

PRESENTATION OF THE HOST STRUCTURE

The Centre de Recherche de l’École de l’Air (CREA) is the multidisciplinary research unit of the Air and Space Academy. The CREA is composed of about thirty researchers from many disciplines: history, sociology, political science, mathematics, fluid and structural mechanics, cognitive science, computer science, signal processing. Its members conduct academic research with a common object: the determinants of the evolution of the military use of aeronautical and space systems.

It is closely linked to the 701 Air Force Base, which gives it the rare ability to access aeronautical resources such as aircraft or flight zones. It also maintains partnerships with major players in the defense and aeronautics sectors (DGA, CEA, ONERA, Dassault Aviation, ISAE group schools, IRSEM, etc.). Associated to the doctoral schools of Aix Marseille University, CREA actively participates in the animation of the PhD program “Defense and Internal Security”. Finally, the proximity of the CEC encourages projects related to digital security.

Restaurant on site. Nurseries and schools in the area. Access to the sports facilities of the Air and Space Academy. Sports and arts club : many activities for executives and families. Very active social and festival committees.

Master's level (M2) in mechanics (preferably from an engineering school); knowledge in aeroelasticity or aerodynamics desired; interest in numerical approaches (MATLAB or PYTHON) and solution techniques.