Genetic optimization and experimental validation of a camber morphing winglet

• Ano de defesa: 2019
• Autor(a) principal: Eguea, João Paulo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Winglet; Algoritmo genético; Arrasto induzido; Estruturas adaptáveis; Genetic algorithm; Jato executivo; Lift induced drag; Mapeamento de escoamento; Midsize business jet; Morphing structures; Optimization; Otimização; Seven-hole flow mapping
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/18/18148/tde-05072019-144340/

International aviation regulations on emissions are becoming more strict. Improvements goals on fuel efficiency demand development of technologies capable of reducing fuel consumption and gas emissions. Morphing structures capability to adapt their aerodynamic shape for optimal condition in flight brings potential for reduction of aircraft drag and operating fuel consumption, minimizing gas emissions and fuel expenses. This study presents an investigation on the impact of a camber morphing winglet on midsize business jet using numerical simulation and wind tunnel experiments. A genetic algorithm was used to optimize the winglet sections camber for different flight conditions. Optimized geometries achieved total drag reduction of up to 0.58% compared to original winglet for single condition optimization, reaching up to 7 % reduction on consumed fuel on a typical mission. This efficiency improvement allows aircraft to carry 900 kg additional load, comprising the morphing system and extra payload. There is an indication of even better results for applications on a bigger commercial jet. Presented methodology is also suitable for new winglet fixed geometry design or incorporating morphing technology. Aerodynamic balance force measurements showed that optimized winglets increased the wing effective aspect ratio (AReff), reducing the lift-induced drag, and maximum lift coefficient (CLmax). However, maximum lift to drag ratio (L/Dmax) was reduced on CL optimization region due to flow differences between optimization and wind tunnel conditions. Aerodynamic efficiency improvement was found for greater lift coefficients (CL). Reductions on wing tip vortex size and intensity due to winglet installation are seen on measured vorticity map, showing liftinduced drag reduction according to Maskells equation. Parabolic drag polar and Maskells equation methods were used for lift-induced drag calculation, using balance force and flowing mapping data for calculations. The presented concept showed considerable aircraft performance improvement, using a feasible device with greater certification ease than other morphing structures concepts, once the failure of this system would not compromise flight safety. Further investigation using computational fluid dynamics (CFD) and wind tunnel experiments is necessary to develop and test a functional camber morphing winglet device.