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Princeton, NJ, United States

Agency: Department of Defense | Branch: Navy | Program: STTR | Phase: Phase I | Award Amount: 79.99K | Year: 2015

A multi-scale/multi-physics integrated tool will be developed to virtually and qualitatively predict the manufacturing defects in structural thermoset polymer composites through a first-principles based approach. The chemo- and thermo- mechanical properties of the thermoset resin during the autoclave process will be characterized with a reactive force field full atomistic and coarse-grained molecular dynamics. A physics-based mapping between these atomistic properties and the actual autoclave processing parameters will be established through the response surface-based reduced order modeling techniques. Then this physics-based mapping will be adopted in the micro- and macro-continuum level analysis to predict fabrication-induced defects. Through this combined multi-scale/multi-physics approach, a macroscopic defect-distribution map will be created with the indication of defects occurrence of various types in composite product level; note that this information will serve as an initial manufacturing-induced material damage for further damage growth/interaction analysis via the XFEM approach. During the process, extensive verification and validation will be conducted to ensure the accuracy of the multi-scale/multi-physics integrated tool on predicting actual damage distributions. GEM has already secured commitments for technical, verification and validation supports from University of Colorado, Lockheed Martin, NRL, and NIAR for the success of the proposed work.

Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 80.00K | Year: 2015

Global Engineering and Materials, Inc. (GEM) along with its team member Carnegie Mellon University (CMU) propose to develop an isogeometric finite element model creation and analysis toolkit for Abaqus. The isogeometric analysis toolkit for Abaqus (IGAFA) will be developed by integrating existing computer aided design (CAD) software with a customized Abaqus toolkit for automatic model generation and response and failure prediction using a T-spline based geometry description. Polycube-based parametric mapping methods are used to build volumetric T-splines from B-Reps for CAD models of complex free-form surfaces. An unstructured all-hexahedral mesh is converted to T-spline volumes for their applications in isogeometric analysis. The IGAFA toolkit will feature 1) FEM model generation that retains exactly the original geometric description of the solid structure; 2) re-construction of Abaqus user-defined elements using the control points without remeshing; 3) reliable 3D stress/strain prediction using a user-defined high order function; 4) progressive failure evaluation in composite structures using accurate stress/strain predictors; and 5) visualization of stress concentration zones and performance of design alternations without user intervention. Verification and validation of both 3D stress analysis and failure prediction of a composite structure will be performed based on existing test data collected from team members.

Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 80.00K | Year: 2016

A multi-scale/multi-physics integrated tool will be developed to predict fatigue crack initiation and propagation in a metallic structure by bridging the length scale from its polycrystals microstructure to a smeared continuum of its complex geometry. In order to simulate the microstructure and localized plasticity driven crack initiation, its micro-growth within a grain or across several grains, and its macro-growth that leads to the final rupture of an aircraft structural component, a fast Fourier transform (FFT) based computational approach integrating phase-field method (PFM) and crystal plasticity (-pro) developed by Prof. Chens research group at the Pennsylvania State University (PSU) will be enhanced and integrated with our 3D extended finite element toolkit for Abaqus (XFA3D). The effects of plasticity will be included for characterization of crack nucleation, its transition to a short crack, and its transition from a short crack to a long crack that will be governed by a linear fracture mechanics theory. A well balanced modeling accuracy and computational efficiency along with our newly implemented isogeometric solution capability in the integrated toolkit will offer its broad use for life prediction of large scale complex structures. GEM has already secured commitments from PSU for the success of the proposed work.

Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase II | Award Amount: 323.43K | Year: 2016

ABSTRACT: Global Engineering and Materials, Inc. (GEM) along with Columbia University propose to develop a simulation tool for modeling mixing process of multi-particle composite systems and generating the ultimate microstructure. A combined theoretical, numerical, and experimental approach will be developed to create a high fidelity software product with a reduced order modeling capability for an optimal exploration of a full scale mixing process. Our innovative approach consists of a novel combined local and global homogeneity identification metrics, an advanced multi-scale model for large scale mixing simulations, a high fidelity DEM/SPH coupling module for high shear mixing of suspensions, a two-scale simulation framework to bridging the continuum and discrete description of an interactive solid particle and fluid system, a parallelized code base that enables both GPU and CPU computing, and customized case study wizard within a GUI to streamline the model generation and solution process for both experienced and inexperienced users. The resulting Particle Dynamics Parallel Simulator (PDPS) toolkit will be validated using test data of multi-particle systems with different solid loads and fluid contents. The validated toolkit will be used to establish a design table for users to describe the trade space as a function of system properties and mixing parameters.; BENEFIT: The results from this research will have significant benefits and broad commercial applications in the Air Force, DoD labs, food, pharmaceutical, catalysis, mineral and other related industries. The results from Phase II will result in an enhanced and fully validated software package for a more heterogeneous system with up to six particle types under realistic mixing scenarios. The proposed DEM/SPH, two-scale solution algorithm and the parallelized software package will provide customers with the key functionality and performance to realize maximum productivity benefits, from engineering simulation to product design. By incorporating the proposed computational algorithms and the high fidelity software product into the design workflow, industries may reduce testing costs significantly while increase the productivity and reliability of the equipment and processes. The finalized software will have an easy-to-use GUI and case wizard that simplify model setup and speeds up simulation set-up time.

Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase II | Award Amount: 746.51K | Year: 2012

A fully coupled fire-structure interaction module will be developed and implemented within GEM"s Abaqus Fire Interface Simulator Toolkit (AFIST) for fire response prediction in aluminum ship structures. This enhanced AFIST will be able to characterize a 3D complex geometry where its topology is not in conformation with a rectilinear CFD grid. An immersed boundary method developed by NIST will be generalized and integrated with the customized Fire Dynamics Simulator. A sharp interface characterization of the solid boundary will be created and the mapping of the boundary conditions from the interface to its immersed boundary nodes will be constructed through local interpolation. A kinematic description of the moving boundary will be accomplished via its coupling with Abaqus. GEM has secured commitments for the joint tool development and validation support from NIST and Virginia Tech, and application guidance from SGH and Navy Lab. The Phase II studies consist of the implementation of the immersed boundary method in AFIST, enhancement of material characterization of marine aluminums in AFIS, verification of the accuracy of the improved coupling method, exploration of the effects of structural deformation on the local flow field, and performance of structural level validation using NICOP and VT"s pool fire test data.

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