Multiobjective composite material design using the variable fidelity model management optimization framework Conference Paper uri icon

abstract

  • Design tool development for multiple phase material design is key to understanding the effect of reinforcement particles on the behavior composites. The increasing computational requirements of advanced numerical tools for simulating material behavior can prohibit direct integration of these tools in a design optimization procedure where multiple iterations are required. One, therefore, requires a design approach that can incorporate multiple simulations (multi-physics with different input variables) of varying fidelity in an iterative model management framework that can significantly reduce design cycle times. In this research, a material design tool based on a variable fidelity model management framework is applied to obtain the optimal size of a second phase, consisting of silicon carbide (SiC) fibers, in a silicon-nitride (Si3N4) matrix to obtain continuous fiber SiC-Si3N4 ceramic composites (CFCCs) with optimal high temperature strength and high temperature creep resistance. To study the trade-offs between these conflicting design objectives and to explore design options, the optimization problem needs to be formulated with multiple objectives. In the variable fidelity material design tool, complex 3 dimensional (3-D) high fidelity FEM based analyses are performed only to guide the 2 dimensional (2-D) low-fidelity FEM model toward the optimal material design. Traditionally the variable fidelity approach has only been applicable to variable fidelity models with matching input variables and responses. This investigation shows how models with different input design variables can be handled and integrated efficiently by the trust region model management framework in application to the design of multiphase composite materials. Using the variable fidelity material design tool in application to a test problem, a reduction in design cycle times of between 50 and 70 percent is achieved as compared to using a conventional design optimization approach that exclusively calls the 3-D high fidelity model. The pareto optimal design obtained using the variable fidelity approach is the same as that obtained using the conventional procedure. © 2009 by the American Institute of Aeronautics and Astronautics, Inc.

publication date

  • 2009-01-01