Improved Composite Duct Design for Increased Safety Margin or Weight Reduction

"Practical methodologies will be developed to efficiently design nonlinear composite ducts and panels with large anomalies and cutouts for buckling. The analysis system to be devised will be automated and integrated into the ANSYS finite element code usingits macro language capabilities, including optimization with parameterized shell and solid models of subject composite duct systems. Important features to be included in the analysis system are 1) geometric nonlinearity of panels due to initial or loadinduced curvature, and 2) buckling and snap-through. There is an opportunity here to improve the tools to expedite such design, to encourage the use of modern tools in general, and to greatly improve accuracy compared to commonly used approaches. Improvedaccuracy is absolutely critical to more optimized and lighter weight designs of composite structures being implemented for the good of the military and the nation. The tools to be developed under this project will also be useful for non military and nongovernment applications, wherever composite structural optimization (and not just panels) is desired to minimize cost in concert with maximizing robustness. After the initial development, the analysis system will be readily adaptable to additional finiteelement codes besides ANSYS."