Optimization of Aircraft Wings for Gust Loads: Interval Analysis-Based Approach

Abstract

An interval-based approach is presented for the optimization of aircraft structures under dynamic loads. As a specific application, the design is considered by including the effect of uncertainty present in the atmospheric turbulence and other parameters on the dynamic response of the aircraft wing structure. The stresses induced during a gust encounter are considered as the primary behavior constraints. The optimization procedure is illustrated with two examples. One is a symmetric double-wedge airfoil and the other is a supersonic airplane wing. The design parameters of the aircraft wing are assumed to be uncertain which are described as interval quantities. Interval analysis is used in the computation of the objective and constraint functions of the problem. An interval-based nonlinear programming technique is developed for the optimum solution of the two aircraft wings considered. The present methodology is expected to be more realistic compared with the probabilistic and fuzzy approaches in situations where either the probability distribution functions or the preference information for the uncertain design parameters is not available.