Interval-Based Multi-Objective Optimization of Aircraft Wings Under Gust Loads

Abstract

An interval-based modified game theory approach is presented for the multi-objective optimization of aircraft wing structures by including the effect of uncertainty present in the atmospheric turbulence. The methodology is illustrated with two examples: a symmetric double-wedge airfoil, based on a beam-type analysis, and a supersonic airplane wing, based on a finite element analysis. The design parameters of the aircraft wing are assumed to be uncertain and are described by a range of values. Because the interval ranges of response parameters are found to increasewithanincreaseinthenumberand/orrangesofinputintervalparameters,atruncationprocedureisusedto obtainanapproximatebutreasonablyaccurateresponseofthestructure.Aninterval-basedgametheorytechnique, coupledwith interval-based nonlinearprogrammingtechniques, isused fortheoptimum solution of thetwoaircraft wings considered. The present methodology is expected to be useful in all practical situations with conflicting goals/ objectives, and where the ranges of the uncertain parameters are readily available, whereas information on the probability distributions or evidence data of the uncertain design variables may not be easily available.