Static aeroelastic analysis : of wind tunnel model with different fidelity level

This thesis investigates the applicability and performance of two computational tools, ZAERO and ZEUS, for static aeroelastic analysis of aircraft structures. The work was carried out in collaboration with Saab, motivated by the company's ambition to complement its existing high-fidelity analysis tools with more time-efficient methods, without compromising accuracy. A numerical study was conducted using wind tunnel test data as a reference, with a particular focus on wing deformation under varying Mach numbers (M, the ratio of flow velocity to the speed of sound) and angles of attack ($\alpha$, the angle between the aircraft’s reference line and the incoming airflow). Where reference measurements were missing, interpolation techniques were successfully applied and evaluated, especially at $\alpha = 4^{\circ}$. The experimental results confirmed that deformation varies linearly with angle of attack and Mach number in the subsonic regime, with noticeable non-linearities appearing near $M = 0.95$ due to transonic effects. ZAERO, despite employing a simplified linear method, demonstrated unexpectedly good agreement with both wind tunnel and CFD-based results, particularly in predicting the vertical deformation. Analyses at $\alpha = 0^{\circ}$ correctly yielded zero deformation due to symmetry. A modal analysis showed that the first nine modes are sufficient to obtain reliable predictions, with three modes dominating the static deformation response. Although the ZEUS analyses were based on a simplified geometry and excluded features like canards and missile tips, they still produced meaningful results. The findings suggest that ZEUS holds significant potential for future use in static aeroelastic prediction, provided that a more refined model setup is implemented. Overall, this work contributes a validated workflow for static aeroelastic analysis using ZAERO and ZEUS, highlights the strengths and limitations of linear aerodynamic methods, and provides guidelines for efficient model development within early design phases.