Constrained Optimization of a Commercial Aircraft Wing Using Non-dominated Sorting Genetic Algorithms (NSGA)

Abstract: In this paper, optimization of Boeing ۷۴۷ wing has been accomplished for cruise condition (Mach Number=۰.۸۵, Flight Altitude=۳۵۰۰۰ ft), where an optimal wing shape is proposed. Objective functions are minimization of wing weight and drag force that as well as confining design parameters, two functional constrains are applied. The first functional constrain is fuel tank volume in the aircraft wing which supplys the required fuel. The second functional constrain is the lift coefficient that should be equal to the initial lift coefficient. Design parameters are root chord, wing span and wing sweep angle. Non-dominating genetic algorithm has been used in optimization process for one optimal solution, until a set of solutions (pareto front) were obtained for two objective functions. Finally a criterion for selecting a best solution for the aircraft on the pareto frontier is addressed.Keywords: Optimization, Drag force, Wing weight, Multi-Objective Genetic Algorithm, Pareto set