Impact of Aspect Ratio on Structural Integrity and Aerodynamic Performance in Fixed-Wing UAV

Abstract

This research is a systematic investigation of the effect of aspect ratio on the structural integrity and aerodynamic performance of fixed-wing unmanned aerial vehicles (UAVs). Higher aspect ratios are generally associated with greater aerodynamic efficiency, primarily through improved lift-to-drag (L/D) ratios, which are essential for extending flight endurance and optimising fuel consumption. Nonetheless, increased aspect ratios impose significant structural demands, including increased bending moments and torsional stresses. This study uses computational fluid dynamics (CFD) and finite element analysis (FEA) within ANSYS FLUENT to analyse variations in aspect ratios and flight speeds, assessing both aerodynamic lift performance and structural deformation under various conditions. The results highlight a critical balance between aerodynamic optimisation and structural rigidity, and suggest that UAV configurations with high aspect ratios and structurally rigid materials achieve superior endurance and stability.

Keywords

• Aspect Ratio
• CFD
• Static Structure

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