Faculty of Engineering at Hiroshima University participates in JAPAN INTERNATIONAL BIRDMAN RALLY every year since 2002. The human-powered aircraft consists of various members, but main wing is the most important part which produces necessary lifting power most effectively so that human-powered aircraft flies in the sky in that. A ready-made thing has been used for the air foil of the main wing till now. Therefore optimize the whole main wing as a new trial, and finding the air foil of the most suitable solution of this study is aimed. Air foil is expressed with a NURBS curve and XFOIL is used for two-dimensional fluid analysis in this study. As an optimization technique, GA is used. Lift produced by the whole main wing and a moment hanging to the wing root are constraint conditions. The objective functions are that the drag in installation attack angle of 3 degrees is minimized to have high performance in a design speed and that the lift drag ratio from an attack angle 0 degrees to 5 degrees is maximized to have more stable wing performance. And then, the most suitable solutions for two cases are derived. In this study, fluid analysis is limited to a two-dimensional problem and the structural consideration is ignored. In addition, in consideration of a fluid characteristic, two kinds of objective functions are introduced and each solution is found. The comparison and the examination of obtained solutions are performed, and the characteristic of each solution is observed to get. Previously, evaluation of the performance was performed so far after having decided air foil. However, air foil which matched a designed purpose was able to be found. As a result of the optimization in this study, a characteristic was found in each solution.
