Oliviu Sugar Gabor

Low-speed aerodynamic characteristics improvement of ATR 42 airfoil using a morphing wing approach

This paper presents a morphing wing technique for extending laminar flow over the airfoil of the ATR 42 regional transport airplane. The objective is to reduce aerodynamic drag by delaying the transition from laminar to turbulent flow over the airfoil upper surface. The optimization of the airfoil shape is performed for several incompressible subsonic regimes, using a genetic algorithm tool, coupled with the subsonic aerodynamic solver XFOIL. A reduction of the drag coefficient with up to 26.73% and a delay in the transition point of up to 24.81% has been achieved.

Aerodynamic performance improvement of the UAS-S4 Ehecatl morphing airfoil using novel optimization techniques

In this paper, we present a morphing wing concept of the airfoil of the S4 unmanned aerial system, the new optimization methodology and the results obtained for multiple flight conditions. The reduction of the airfoil drag coefficient has been achieved using an in-house optimization tool based on the relatively new Artificial Bee Colony algorithm, coupled with the Broyden–Fletcher–Goldfarb–Shanno algorithm to provide a final refinement of the solution. A broad range of speeds and angles of attack have been studied. An advanced, multi-objective, commercially available optimizing tool was used to validate the proposed optimization strategy and the obtained results. The aerodynamic calculations were performed using the XFOIL solver, a two-dimensional linear panel method, coupled with an incompressible boundary layer model and a transition estimation criterion, to provide accurate estimations of the airfoil drag coefficient. Drag reductions of up to 14% have been achieved for a wide range of different flight conditions, using very small displacements of the airfoil surface, of only 2.5 mm.

Morphing wing application on hydra technologies UAS-S4

This paper presents the aerodynamic results of a morphing wing study performed on the UAS S4 Ehecatl from Hydra Technologies. Only the cruise phase of the aircraft was considered (constant altitude and constant speed). The difference, from an aerodynamic point of view, between the morphing wing and the original wing was emphasized by computing and comparing their longitudinal aerodynamic coefficients (drag and lift). The computation of the aerodynamic characteristics was done using tornado with the Vortex Lattice Method.