Multidisciplinary design optimization of a structurally nonlinear aircraft wing via parametric modeling

Abstract

In this study, the optimization of an aircraft wing design was conducted using multidisciplinary design optimization (MDO), which integrates aerodynamic and structural analysis in considering nonlinear structural behavior. Automation is an absolute necessity to make the MDO framework practical for actual engineering optimization problems. The objective of this research was to develop a fully automated MDO framework in which the entire process is automated through a parametric-modeling approach. The computational fluid dynamics (CFD) grid was generated automatically from parametric modeling using CATIA and Gridgen, followed by automatic flow analysis using FLUENT. The computational structure mechanics (CSM) grid was generated automatically by the parametric methods of CATIA and MSC/Patran. The structure was analyzed by ABAQUS considering the deformation nonlinearity, and the aerodynamic load was transferred from the CFD grid to the CSM grid using the volume spline method. The response surface method was applied for optimization, which helped achieve the global optimum. The developed MDO framework was applied to a wing optimization problem in which the objective was wing weight and the constraints were the lift-drag ratio, wing deflection, and structural stress level. The aspect ratio, taper ratio, quarter-chord sweep angle, skin thickness, and spar flange area were the design variables. The optimization design result demonstrated a successful application of the fully automatic MDO framework.