Simulation-based Design of Mesostructures Manufactured for Hypersonic Flight Conditions

Metamaterials are promising candidates for applications that require high strength and thermal resistance but reduced weight due to the porous topologies of the mesostructures. Hence, the Air Force can improve aircraft performance in hypersonic operating environments by integrating aero-components fabricated with metamaterials, leveraging their suitable strength at extreme flow conditions and with decreased loading. Additive Manufacturing (AM) methods have also improved their technical maturity that they can potentially print the complicated mesostructure topologies to manufacture the required aero-components. To accelerate the manufacturing process of metamaterial-based aero-components, Integrated Computational Materials Engineering (ICME) methods will be applied to design the aero-components in a systematic manner using simulations. Finite Element Analysis (FEA) simulations will model the thermo-structural response of a metamaterial component in the hypersonic operating environments, using Computational Fluid Dynamics (CFD) simulations to predict the extreme temperature and pressure distributions on the surface. The complicated material properties of metamaterials will initially utilize current data in the literature to incorporate the anisotropic mechanical and thermal behavior into the constitutive material models for FEA. The properties will be formulated in a tensor format to properly represent the effects of the anisotropic mesostructure topology. Flight path predictions will also be used to guide the CFD simulations and account for maneuverability. Optimization methods will be coupled to the FEA-CFD simulation codes to rationally down-select the best mesostructures in terms of, for example, sufficient strength in hypersonic flow at reduced weight. Virtually designing and down-selecting the metamaterials will focus the AM efforts to print the aero-component with the most promising candidate materials. The AM workflow will also be surveyed to determine the current capabilities and identify technical gaps that need to be improved for printing mesostructures. The Phase I efforts will establish the framework to improve in Phase II, such as enhancing the AM capabilities, measuring metamaterial properties, developing the improved property tensor-based material models for FEA, and creating the documented and tested modeling workflow with commonly used FEA, CFD, and optimization software. These capabilities will be inserted into AFRL programs to design and manufacture metamaterials in an ICME approach, producing high performing aero-components