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Development of Computational Model of Sport Utility Vehicle PowerPoint Presentation
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Development of Computational Model of Sport Utility Vehicle

Development of Computational Model of Sport Utility Vehicle

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Development of Computational Model of Sport Utility Vehicle

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  1. Development of Computational Model of Sport Utility Vehicle Srdan Simunovic, Gustavo Aramayo and Thomas Zacharia Computer Science and Mathematics Division Oak Ridge National Laboratory NHHTSA Project Review, October 20 1998

  2. http://www-explorer.ornl.gov

  3. Outline • Status • Modeling Approach • Available Models • Things to Finalize

  4. Status • Developed parametric finite element model of 1998 Ford Explorer XLT 4x2 • Tested models • full frontal impact • frontal offset impact • frontal offset oblique impact • Developed WWW-based model manipulation • WWW based model generation available 12/98

  5. Related Parametric FEM Projects at ORNL • Aluminum Intensive Vehicle Model Development • Ultra Light Steel Auto Body

  6. Aluminum Intensive Vehicle

  7. ULSAB

  8. Fixed FEM Mesh Model • Initial FEM model was based on “dirty” geometry • scanned geometry was not extensively modified • regularity and connectivity of FEM mesh was enforced by direct placement of nodes on surfaces and by single FEM mesh realization • Model has varying degree of FEM mesh regularity and quality • frame - high • body - low • Model was tested in frontal and frontal-offset impact

  9. Fixed FEM Model Features • 25k Nodes, 25k Elements • Relatively good results • good deformation, crash duration, acceleration • mainly due to importance of frame in impact response • Model modifications not practical • regularity enforced by numerous ad-hoc constraints

  10. Parametric FEM Model • Objective • More FEM meshes in less time • Methodology developed can be easily applied to other FEM models • Want to learn more on vehicle impact simulations • Have not been done yet for such complex models

  11. Advantages of Parametric Model • Rapid generation of crash situation-specific models • Simple model modification through parameter modification • Allows for investigation of convergence of simulation results • Becomes possible to determine “the best” model for specific impact scenario

  12. Disadvantages of Parametric Modeling Approach • Longer initial model development time • Geometry needs to be “clean” • Software not yet available for entire process • Manipulation of large number of parameters is cumbersome, therefore, model modification is usually limited to initial developers

  13. Coarse FEM Mesh

  14. Frontal Impact Model

  15. Rear Impact

  16. Frontal Impact

  17. FEM Mesh Parametrization • Clean up geometry • connections between CAD surfaces must be accurate • CAD surfaces must be reorganized to fit FEM model • Pick up general mesh topology • For each part develop FEM mesh projection approach • Determine topology constrains enforced by neighboring parts • Create FEM mesh through projections on CAD surfaces

  18. FEM Mesh Parametrization • Enforce FEM mesh connectivity through part boundaries by mesh topology constraints • Make FEM mesh projections using CAD entities, not coordinates • Make things as you go • CAD, FEM mesh, mesh generator scripts, parsers, CAD-to-FEM-to-CAD, visualization • Debug!

  19. Basic FEM Model

  20. Coarse FEM Mesh

  21. Basic Model - Results

  22. Frontal Impact Model

  23. Frontal Impact - Results