MLA is a multidisciplinary problem involving the coupled physics of aerodynamics, flight dynamics, and structural analysis. This work presents an analytical model-based investigation of MLA through movable control surfaces for various wing platforms, aiming to understand the underlying physics, identify key influencing parameters, and inform the formulation of associated multidisciplinary optimization problems. The investigation starts with a rigid wing and a single-point aileron, and incrementally increases modeling complexity by introducing finite aileron span, aircraft trim conditions, alternative lift distributions (e.g., Prandtl’s Bell-Shaped) and wing flexibility to further improve the fidelity. Key findings reveal that optimal aileron placement for load alleviation is highly sensitive to trim effects, shifting from approximately 71% span for a rigid wing to 82% span when trim is considered, and further to 64.33% span for a trimmed wing with a Bell-Shaped lift distribution. Trim effects are identified as the dominant factor due to compensatory pitch angle changes, while wing planform (lift distribution) also has a significant influence. In contrast, the aileron span and wing flexibility (for straight wings) exhibit comparatively minor impacts on optimal placement. Furthermore, the analysis demonstrates that while flaps can also achieve load alleviation with optimal placement near the wing root, the optimal aileron placement is independent of flap usage. These analytical insights provide foundational understanding, crucial for guiding preliminary aircraft design and streamlining subsequent computationally expensive high-fidelity Multidisciplinary Design Optimization (MDO) efforts.
Code associated with the paper: https://arc.aiaa.org/doi/10.2514/1.C038643
Megson, T. H. G. (2012). Aircraft structures for engineering students. Elsevier.
@book{megson2012aircraft, title={Aircraft structures for engineering students}, author={Megson, Thomas Henry Gordon}, year={2012}, publisher={Elsevier} }