Design Optimization and Higher Order FEA of Hat-Stiffened Aerospace Composite Structures

Sizing of hat-stiffened composite panels is challenging because of the broad design hyperspace in several geometric and material parameters available to the designer. Design tasks can be simplified if parameter sensitivity analysis is performed a priori and design data is made available in terms of a few important parameters. In this chapter, design sensitivity analysis is performed using finite element analysis (FEA) and analytical solution models. Manufacturing and experimental measurements of a hat-stiffened composite structure is performed to validate the FEA and idealized analytical solutions. This is an attempt to initiate a structural architecture methodology to speed the development and qualification of composite aircraft that will reduce design cost, increase the possibility of content reuse, and improve time-to-market. In particular, FEA results were compared with analytical solutions to develop a design methodology that will allow extensive reuse of parametric hat-stiffened panels in the design of composites structural components. This methodology is now widely utilized in developing a library of commonly used, built-in, composite structural elements in design of modern aircrafts. In this chapter, hat stiffened composite panels’ geometric parameter sensitivity analysis work were parametrically investigated using finite element analysis (FEA), analytical solution models and experimental testing on manufactured parts in order to develop structural architectures that speed development and qualification of composite aircraft which has broad benefits in reducing cost, increasing content reuse and improving time-to-market. In particular, FEA results were compared with analytical solutions and a design methodology was developed to allow extensive reuse of parametric elements in structural design of composites and to achieve expedited design, verification, validation, and airworthiness certification and qualification. The goal of this work is to provide the aviation industry with the most up-to-date databases for the application of advanced composite materials incorporated into parametric models to eliminate redundancies in the current process. The work results include a correlated material database, an optimized model component library and a standardized way to design future complex composites structures, e.g. hat stiffened composites panels, with reliable and predictable quality and material weight/cost