SBIR-STTR Award

The objective of the proposed work is to develop a tool for real-time interactive visualization of the results of combined CFD and multibody dynamics simulations of tanker vehicles and sloshing liquid payloads. The tool can be used for the following: 1) visualization of an animation of: liquid surface, iso-surfaces, vehicle, terrain and surroundings; 2) making any part of the model semi-transparent so that obstructed parts are visible; 3) coloring/contouring the surface of the tank, an iso-surface, a cutting plane, or any other surface in the fluid domain using a scalar response quantity, 4) placing animated arrows on a surface or volume in the fluid domain, 5) visualization of volume and surface-restricted streak-lines, path-lines, and time-lines, and 6) flow feature extraction including visualization of vortex cores and separation/attachment lines. The user will be able to view the animation from a ground viewpoint or a viewpoint attached to the vehicle. The simulation can be viewed on multi-screen immersive stereoscopic displays. The tool will run on Windows, Unix, and Linux platforms. Finally, the tool will include a hierarchical clickable list of natural-language commands, the ability to process the user's natural-language speech, and multimedia-enhanced step-by-step guiding for inexperienced users

The objective of this proposal is to develop a tool for time-accurate simulation of coupled CFD and multibody dynamics of tanker vehicles and sloshing liquid payloads, that includes integrated pre-processor, solver, and post-processor. The pre-processor allows constructing an object-oriented hierarchical "preliminary" model of the vehicle, tank, and terrain. The pre-processor includes a model tree editor along with interactive display of the model. It also includes an automatic mesh generator for generating the finite element (FE) model from the preliminary model. The FE model consists of hexahedral, beam, and truss solid elements, rigid bodies, joints, hexahedral incompressible fluid elements, and quadrilateral fluid-solid interface elements. The fluid mesh is modeled using a very light and compliant solid mesh which allows the fluid mesh to move/deform along with the tank using the ALE formulation. The fluid's free-surface is modeled using a mass conserving volume-of-fluid based algorithm. A parallel explicit-time integration solver is used to generate the coupled dynamic response of the vehicle, tank, and fluid. The post-processor allows near-photorealistic visualization of animations of: 1) liquid free-surface, iso-surfaces, vehicle, terrain and surroundings; 2) colored/contoured surfaces, 3) surface/volume arrows, 4) stream/streak/path-lines. Users can control the visualization using the tree editor or a clickable hierarchical list of natural-language commands.

Keywords:
Flexible Multibody Dynamics, Computational Fluid Dynamics, Fluid-Structure Interaction, Liquid Sloshing, Tanker Vehicles, Coupled Multibody-Fluid Simu