Several computational tools for aircraft design are being developed in this program. These include improved methods for aircraft synthesis and optimization such as S. Wakayama's thesis work on wing planform optimization, described below.
A method is being developed for optimizing wing planform shapes for subsonic transport aircraft. Aerodynamic and structural analyses are integrated with a sequential quadratic programming optimizer to yield successful wing planform optimization. The aerodynamic drag analysis considers induced, profile, and compressibility drag. An advanced structural analysis was developed to evaluate wing weight and stiffness through consideration of bending strength and buckling constraints at multiple design conditions. Effects of static aeroelasticity and bending relief due to fuel inertia are also evaluated in the structural analysis. Maximum lift is calculated through a critical section analysis, with a correction for induced camber developed to handle flapped wings.
The method generates realistic planform designs and has been used to study non-planar wing tips and effects of designing for natural laminar flow on a business jet. Further development has extended the method to wing-tail combinations, with constraints on trim, static margin, and gear placement.