Aeroelastic Modeling of Deformable-Airfoil Wings Through Unsteady Lifting-Line Theory
Riccardo GIANSANTE, Giovanni BERNARDINI, Massimo GENNARETTI
Abstract. This paper presents a state-space formulation for the aeroelastic stability analysis of deformable-airfoil wings. The proposed approach couples the wing structural dynamics modeled as a cantilever plate (through an FEM approach) with aerodynamic loads computed through an Unsteady Lifting-Line Theory (ULLT), which evaluates the unsteady sectional loads using the Küssner-Schwarz and accounts for wake effects through the Biot–Savart law. The corresponding bound circulation is obtained via the Kutta–Joukowski theorem extended to unsteady flows. The distributed aerodynamic loads are projected onto the shape functions introduced in a Galërkin solution approach, thus yielding an aerodynamic operator expressed through transcendental transfer functions, which is then approximated into a rational state-space form. This enables straightforward aeroelastic stability assessment through eigenvalue analysis and provides a framework suitable for control design. The model’s accuracy is validated using the paper flutter problem, whose aeroelastic behavior is representative of deformable-airfoil wings.
Keywords
Unsteady Aerodynamics, Aeroelasticity, State-Space, Lifting-Line Theory, Morphing Wings, Paper Flutter, Flag Flutter, Finite Element Method
Published online 7/20/2026, 5 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Riccardo GIANSANTE, Giovanni BERNARDINI, Massimo GENNARETTI, Aeroelastic Modeling of Deformable-Airfoil Wings Through Unsteady Lifting-Line Theory, Materials Research Proceedings, Vol. 69, pp 370-374, 2026
DOI: https://doi.org/10.21741/9781644904251-67
The article was published as article 67 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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