Team for Advanced Flow Simulation and Modeling
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Large-Scale Fluid-Particle Interactions
The mathematical modeling in these simulations is based on the time-dependent Navier-Stokes equations governing the flow around the particles and Newton's law of motion governing the 3D dynamics of the particles with the fluid forces acting on these particles calculated from the flow field. In these simulations, while the mesh partitioning, flow computations, and mesh movements are performed on a 512-node CM-5, the mesh generation and projection is accomplished on a 20-processor SGI Onyx system. The two platforms communicate via a HiPPI channel. The spheres, in addition to interacting with the fluid, interact and sometimes collide with each other and with the tube wall. We simulated two cases: with the size of the spheres random in one case and uniform in the second. In both cases, the simulation is started with the spheres distributed randomly in the tube. The mesh sizes during these simulations reach 1.2 million tetrahedral elements (resulting in approximately 2.6 million coupled, nonlinear equations to be solved at each time step), and the number of time steps is around 800 for each simulation. The average Reynolds number is approximately 40 in both cases. The figure here shows the random-sized spheres at four different instants during the simulation. These simulations show how the advanced computational methods developed, together with modern parallel computing platforms, enable us to carry out this difficult class of simulations at levels that would have been unthinkable a few years ago. This simulation tool can be used to help understand the behavior of fluid-particle mixtures which are used in many practical applications. The unstructured mesh generator, flow solver, and flow visualization software (based on Wavefront) were developed by the T*AFSM.
1. T.E. Tezduyar, "Stabilized Finite Element Formulations for Incompressible Flow Computations", Advances in Applied Mechanics, 28 (1991) 1-44.
2. T.E. Tezduyar, M. Behr and J. Liou, "A New Strategy for Finite Element Computations Involving Moving Boundaries and Interfaces--The DSD/ST Procedure: I. The Concept and the Preliminary Numerical Tests", Computer Methods in Applied Mechanics and Engineering, 94 (1992) 339-351.
3. T.E. Tezduyar, M. Behr, S. Mittal and J. Liou, "A New Strategy for Finite Element Computations Involving Moving Boundaries and Interfaces--The DSD/ST Procedure: II. Computation of Free-surface Flows, Two-liquid Flows, and Flows with Drifting Cylinders", Computer Methods in Applied Mechanics and Engineering, 94 (1992) 353-371.
4. A.A. Johnson and T.E. Tezduyar, "Simulation of Multiple Spheres Falling in a Liquid-Filled Tube", Computer Methods in Applied Mechanics and Engineering, 134 (1996) 351-373.
5. A.A. Johnson and T.E. Tezduyar, "3D Simulation of Fluid-Particle Interactions with the Number of Particles Reaching 100", Computer Methods in Applied Mechanics and Engineering, 145 (1997) 301-321.
6. T. Tezduyar, "CFD Methods for Three-Dimensional Computation of Complex Flow Problems", Journal of Wind Engineering and Industrial Aerodynamics, 81 (1999) 97-116.
7. A. Johnson and T. Tezduyar, "Advanced Mesh Generation and Update Methods for 3D Flow Simulations", Computational Mechanics, 23 (1999) 130-143.
8. T. Tezduyar and Y. Osawa, "Methods for Parallel Computation of Complex Flow Problems", Parallel Computing, 25 (1999) 2039-2066.
9. A. Johnson and T. Tezduyar, "Methods for 3D Computation of Fluid-Object Interactions in Spatially-Periodic Flows", Computer Methods in Applied Mechanics and Engineering, 190 (2001) 3201-3221.