Continuum Shape Sensitivity with Spatial Gradient Reconstruction of Nonlinear Aeroelastic Gust Response

Abstract

Accurate modeling of the aeroelastic response due t o gust loads is becoming a design necessity for many novel concepts. Both the high a spect ratio wings of high altitude long endurance (HALE) aircraft and flexible membrane wings of micro aerial vehicles (MAVs) are susceptible to large deformations, geometric no nlinearities, and rigid body motion when gust loads are encountered. Using gradient based o ptimization for aeroelastic shape design of such configurations can be computationally expensive. Furthermore, multidisciplinary design optimization frameworks that use gradient-based algorithms are becoming increasingly popular. A major challenge in developing such frameworks is implementing accurate and efficient sensitivity analyses for the various disciplines. This becomes especially challenging when a “black box” analysis tool is used and access to the source code is not possible. Presented in this paper is a cont inuum shape sensitivity method which does not require access to or knowledge of source code f ormulation. A static nonlinear beam bending problem and a static linear plate bending p roblem are presented as benchmarks. In addition, continuum shape sensitivities are compute d for an aeroelastic gust response of both a one- and two-dimensional structure. In all cases , the analysis tool is treated as a “black box”.