## Team for Advanced Flow Simulation and Modeling |

For more information: |
## Flow Past a Ram-Air Parachute
The introduction of ram-air parachutes marked a turning point in parachute design. In military applications, current airdrop methods expose delivery aircraft to low-altitude enemy air defense threats as they fly directly over the target area to ensure drop zone accuracy. Future airdrop systems require the development of very large gliding parafoils capable of delivering up to 21 tons from altitudes as high as 25,000 feet with automated navigation, increased accuracy, and reduced ground impact velocity. The dynamics of deploying a parafoil canopy of this size is presently not fully understood and thus presents a major technical barrier. Also, parafoils of this size have never been flown nor do wind tunnels exist that could be utilized to obtain information on the aerodynamic performance of the parafoil or on the response of the parafoil to control inputs. Advances in recent years in high performance computing allow computational fluid dynamics to be used to study both the inflation and steady-state performance of large gliding parafoils. The picture above shows the pressure distribution on the surface of the parafoil. The mesh used to obtain this solution in the picture above consists of 144,649 nodes and 905,410 tetrahedral elements. This computation was carried out on a CRAY T3D supercomputer. The unstructured mesh generator, flow solver and flow visualization software (base on Wavefront) were developed by the T*AFSM.
The picture below appeared on the
cover of the 1994 Summer edition of the IEEE
The picture below appeared in the 1995 Calendar of the Supercomputing '94 conference.
The movie shows the pressure distribution on the surface of the structured mesh as it expands from a rectangular box. ## References: 1. T.J.R. Hughes, T.E. Tezduyar and A.N. Brooks, "Streamline Upwind
Formulations for Advection-Diffusion, Navier-Stokes, and First-order
Hyperbolic Equations", 2. T.E. Tezduyar, "Stabilized Finite Element Formulations for
Incompressible Flow Computations", 3. T.E. Tezduyar, S. Mittal and R. Shih, "Time-accurate
Incompressible Flow Computations with Quadrilateral Velocity-Pressure
Elements", 4. S. Mittal and T.E. Tezduyar, "Parallel Finite Element Simulation
of 3D Incompressible Flows--Fluid-Structure Interactions",
5. T.E. Tezduyar, M. Behr and T.J.R. Hughes, "High Performance Finite
Element Computation of Fluid Dynamics Problems", 6. T. Tezduyar, S. Aliabadi, M. Behr, A. Johnson, V. Kalro and M.
Litke, "Flow Simulation and High Performance Computing", 7. S. Mittal and T. Tezduyar, "Finite Element Simulation of Large
Ram-Air Parachutes", 8. T. Tezduyar, "Advanced Flow Simulation and Modeling", 9. R. Benney, K. Stein, V. Kalro, T. Tezduyar, J. Leonard and M.
Accorsi, "Parachute Performance Simulations: A 3D Fluid-Structure
Interaction Model", 10. T. Tezduyar, "CFD Methods for Three-Dimensional Computation of
Complex Flow Problems", |