Software for the Design and Certification of Unitized Airframe Components

An investigation of the feasibility of commercialization of the results developed in the Center for Computational Mechanics, Washington University, St. Louis, Missouri under AFOSR Grant No. F49620-01-1-0074 entitled; "Mathematical and Computational Framework for a Virtual Fabrication Environment for Aircraft Components". The proposed project will address some of the key requirements identified in the report Uninhabited Air Vehicles: Enabling Science for Military Systems (National Materials Advisory Board, Aeronautics and Space Engineering Board, US Academy of Sciences, 2000). Specifically, an investigation of mathematical models for the simulation of structural stability and post-buckling responses of light-weight unitized airframe components fabricated from aluminum plates by high speed machining techniques will be undertaken. It has been observed in machining experiments that some thin-walled components exhibit local buckling even in the unloaded condition, due to residual stresses. Therefore the effects of residual stresses and the initial configuration have to be taken into account in simulations performed for the purposes of design and analysis. The goal of this project is to investigate the feasibility of development of a comprehensive software tool for the design and certification of metallic unitized airframe components based on the hierarchic concept of working models, incorporating the effects of residual stresses.