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Xflr5 half wing3/25/2023 ![]() ![]() This thesis deals with aerodynamic optimization of morphing wings under performance and geometric constraints. For these results density and velocity are taken as 1.225 kg/m 3 and 30 m/s. Comparison of pan3d.f results with XFLR5 in terms of pressure distribution is illustrated in Figure 2, while the comparisons of lift coefficient (C L ) and induced drag coefficient (C Di ) for half wing, can be seen in Table 1. With the help of the formulations in, a Fortran code (pan3d.f) was developed, which can model wing for different NACA airfoils, root chord (c r ), half span (b/2), taper ratio ( λ ), leading edge sweep angle ( Λ ), dihedral angle ( Γ ), incidence angle( θ ) and twist angle ( φ ) values, and various tests were performed by comparing the results with XFLR5, whose prediction is in good agreement with the experimental results. Kutta condition is satisfied by defining wake panels using the doublet strengths of the panels at trailing edge. By using Dirichlet boundary condition, source strengths are fixed by using free stream potential and doublet strengths are remained as unknown. A panel method solver that has constant source and doublet distribution as singularity elements on each panel is developed. In this study, panel method and empirical formulas for laminar and turbulent boundary in order to find c f are coupled with GRGM in order to define a minimization function and constraints for the optimization problem. The ability of wing morphing promises the following improvements: improved performance covering the entire flight envelope, simplification of conventional control surfaces and their mechanisms, improvement of the quality of the flow field surrounding the vehicle which will result in drag reduction and lift increase, reduction of manufacturing costs, reduction of the vehicle empty weight, hence improved payload capacity and fuel economy. Contrary to this, due to success in advancing smart materials, including sensors, actuators, and their associated support hardware and micro-electronics, in recent years, there has been a growing interest in “morphing aircraft” which are defined at NASA Reports as the aircraft that are utilizing wings that have the capability to drastically change planform shape during flight – perhaps a 200% change in aspect ratio, 50% change in wing area, and a 20 degree change in wing sweep. This situation brought the world into today’s current aircraft configurations, which are designed and optimized for one or only a few flight conditions with fixed wing geometry, Figure 1. ![]() However, during the progress in aviation, wings of the birds cannot be mimicked due to lack of advanced materials and mechanisms. Aviation adventure of human being was always inspired by the flight of birds. As a result of design process, it is found that 16.733% increase in aircraft range can be achieved compared to the original wing. GRGM is developed and validated with a milestone problem in optimization studies. Michel’s 1 st formula is used for transition prediction. Empirical laminar and turbulent skin friction coefficient formulas are used for parasite drag prediction. Panel method is developed and validated with XFLR5, which is itself based on the panel method. A rectangular baseline wing geometry is optimized for maximum range by varying its thickness and camber distribution at cruise speed (30 m/s) using spline method. original wing, optimized wing and a morphing wing for an experimental UAV. Result that is obtained with this tool is compared for three different wing configurations, i.e. The computational tool involves a panel method, empirical relations for laminar and turbulent boundary layers in order to find the skin friction coefficient values (c f ) and a gradient based generalized reduced gradient method (GRGM). this study, an aerodynamic optimization tool is discussed.
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