Friday, February 14, 2014
Overview of Integrated, Multiscale Modeling Capabilites at Glenn Research Center
Steven Arnold, Chief, Mechanics and Life Prediction Branch, Structures and Materials Division, NASA Glenn Research Center
The Integrated Multiscale Micromechanics Analysis Code (ImMAC) Software Suite consists of three components for the design and analysis of composite structures: 1) the Micromechanics Analysis Code with Generalized Method of Cells (MAC/GMC) performs rapid analysis of composite materials and laminates based on non-FEA micromechanics methods; 2) FEAMAC couples the efficient micromechanics capabilities of MAC/GMC with the Abaqus finite element code for multiscale analysis of composite structures; and 3) HyperMAC couples the MAC/GMC micromechanics capabilities with the HyperSizer stiffened structural optimization software. This talk will provide an overview of capabilities and more importantly our philosophy on conducting multiscale analyses. The ImMAC software, in which the generalized method of cells (GMC) micromechanics approach is used to model the local composite material behavior either at integration points within i) each ply of a given laminate or ii) within each finite element comprising a given composite structure via the Abaqus user-definable subroutines. GMC localizes to the level of the fiber and matrix constituent materials, and thus enables the use of arbitrary nonlinear constitutive, damage, and life models (many of which are provided by MAC/GMC) for each monolithic phase throughout the composite laminate/structure. This circumvents the need for effective anisotropic constitutive models for the composite materials within the laminate/structure, which can be difficult to obtain and characterize in the presence of material nonlinearity. Further, GMC provides access to the constituent level stresses and strains throughout the structure, enabling the use of fiber and matrix scale failure and damage evolution criteria. The well-documented computational efficiency of the GMC micromechanics approach (as compared to the finite element micromechanics approach, for example) is an important asset that permits the tractability of coupled structural FEA-micromechanics problems.