Refinement of Glider Aerodynamic Design using CFD

Abstract

Only small aerodynamic improvements are possible on current sailplane designs when using current design and analysis methods. In order to obtain a substantial improvement in cross-country performance, areas which are not fully optimized must receive attention. These areas include regions where complex flows exist on the surface and special analysis tools are required. New developments in CFD laminar to turbulent transition modeling allow optimization of complex 3-D flow areas such as the wing-fuselage junction. To demonstrate the overall effect of using CFD to optimize many small areas around the sailplane, the total performance improvement was compared against a baseline sailplane. The possible performance improvement for an 18m Class sailplane was calculated and found to be around 3 glide-ratio points.