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In this work, a Sequential Decision Process (SDP) is applied to perform fuselage design using Computational Fluid Dynamics (CFD). The SDP uses models to provide two-sided estimates that attempt to bound the exact solution, ultimately converging to an optimal design space to be analyzed with models of increased fidelity. The present work proposes the use of laminar and turbulent physics in CFD models to form lower and upper bounds on drag calculations, respectively. These bounding models are then used in a formal SDP to cull the design space, focusing the region of interest for increased fidelity modeling and analysis. Increasing mesh resolution is used to increase fidelity, creating a multi-fidelity approach to aerodynamic shape design. In this work the SDP-CFD design approach is applied to two design problems: (1) drag minimization of a fairing with a defined thickness and (2) drag per unit volume minimization of a fairing. The results of this study demonstrate that the SDP-CFD approach can accurately and quickly improve the fuselage design.

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The objective of this study is to characterize the trade space for the structural design of small uncrewed aerial vehicle wings fabricated using Material Extrusion Additive Manufacturing, specifically the trade-off between maintaining the wing external shape while minimizing its internal structure. Beam bending analysis shows that the structural requirements associated with flight loads are easily met with a single perimeter extrusion monocoque construction, however this approach leads to large, unsupported, thin-walled structures that can deform during the build process, creating a potential need for additional structure to maintain wing shape. To characterize the relationship between structure/weight and wing deformation, wing sections were fabricated with varying internal structures for two airfoil shapes. Weight and 3-D laser measurements were taken of the printed parts to capture the final as-built geometry. The as-built geometries were then compared to the as-designed geometries to quantify the deformation, and a coupled viscous-inviscid flow solver was used to determine the aerodynamic effects. The results indicate that while significant aerodynamic performance penalties exist for the monocoque construction, a small amount of well-placed internal structure provides sufficient improvement at minimal weight penalty. Results also showed that less internal structure is required to minimize deformation for an airfoil with larger initial curvature.