Combined structural and manufacturing optimization of stiffened composite panels

Manufacturing considerations have been incorporated into the design optimiz ation of a blade-stiffened composite panel. For the manufacturing analysis, a one-dimensional resin film infusion model is developed to compute the in filtration time of the resin into a fabric preform of the panel. Results ar e presented showing the effects of design variables that are important for structural performance, such as cross-sectional geometry variables and mate rial properties, on the panel manufacturing effort. In addition, the effect s of manufacturing process variables, such as pressure and temperature, on the structural performance are studied. The structural problem is formulate d to minimize the panel mass subject to buckling constraints. A simplified buckling analysis model for the panel is used to compute the critical buckl ing loads. The objective of the manufacturing problem is to minimize the re sin infiltration time. Optimum panel designs for the manufacturing and stru ctures problems alone, as well as for the combined problem, are generated u sing a genetic algorithm. The results indicate a strong connection between the structural and manufacturing design variables and tradeoffs between the two responses, and illustrate that a multidisciplinary approach to the pro blem is essential to incorporate manufacturing into the preliminary design stage.