TAFSM uses EnSight visualization software to assess paratroopers' jumping from a cargo plane traveling at 130 knots.

Among these questions are: What is the airflow around the plane when the paratrooper is exiting through the door? How will unsteady airflow affect the jump? What aerodynamical forces are exerted on the paratrooper at different times? What are the aerodynamics of a paratrooper with an open parachute?

TAFSM members include computational scientists from Rice University, Clark Atlanta University, Network Computing Services, the Army HPC Research Center, and the U.S. Army Natick Research, Development & Engineering Center.

Airdrop simulations demand that millions of coupled nonlinear equations be solved for each time step. "The size of the simulations has always been a major computational challenge for us," says TAFSM leader Tayfun E. Tezduyar, James F. Barbour Professor of Engineering and chairman of the Department of Mechanical Engineering and Materials Science at Rice University. A 256-processor Cray T3E-1200 supercomputer and Silicon Graphics multiprocessor systems supply the processing power for TAFSM's work.

One animated sequence depicts jump. Color bands show aerodynamic pressure distribution on plane.

A pair of scenarios are simulated to analyze the real-world factors that influence parachute design and paratrooper deployment. One scenario depicts the aerodynamics and dynamics of a paratrooper jumping from a cargo plane traveling at 130 knots. TAFSM uses its own space-time finite-element formulation and mesh-moving algorithms to numerically simulate the problem on the Cray. The other simulation calculates the airflow past an open parachute over time. Once computations are carried out on the Cray, data is imported into EnSight, a visualization program from Computational Engineering International. TAFSM's visualizations use EnSight's support for large, unstructured tetrahedral meshes that deform and change connectivity over time. The models can contain up to 40 million elements.

Animation shows airflow past an open parachute over time. It includes about 1,300 time steps.

In the aircraft/paratrooper scenario, the EnSight visualizations use color bands to show the aerodynamic pressure distribution on the paratrooper and the aircraft's surface. The position and orientation of the paratrooper are shown at different instants during the simulation.

The open parachute simulation includes about 1,300 time steps, or 65 seconds of real time. The EnSight visualization displays path lines colored with the magnitude of velocity starting at the same location for three different instants. It also shows surface pressure distribution at the instant the path lines were started.

A Silicon Graphics Onyx2 Infinite Reality2 with two CPUs and a 20-CPU Onyx Reality Engine II are used to compute TAFSM's visualizations. TAFSM outputs the visualizations in real 3-D so that they can be viewed with StereoGraphics' CrystalEyes eyeware. Stereo 3-D graphics helps researchers to understand flow simulations by placing themselves inside complex geometry.

Although they may never jump out of an aircraft themselves, TAFSM researchers are providing technical help (if not emotional support) to those who will.

The Coors/Coors Light Chevrolet Monte Carlo, driven by two-time Daytona 500 winner Sterling Marlin, has improvements designed using Algor software.

Erwin had two optimization goals: increasing the stiffness of the chassis and lowering the center of gravity for better handling and stability. Erwin set out to decrease chassis deflection in laboratory testing by 50 percent, or 1/32-inch, using Algor's modeling and analysis tools. He went about lowering the center of gravity by modifying the frame structure and displacing weight from the chassis to the base of the car while maintaining the mandatory total weight of at least 3,400 lbs. required by Winston Cup officials.

The first step was to model the length and width of the main frame rail with beam elements using Algor's Superdraw III. Next, the firewall and floor pan sections were modeled with plate elements to create a combined 3-D beam/plate model. Erwin used two load cases to analyze overall deflection in his model. One load case contained lateral loading placed on the track bar mount, which connects the track bar to the rear subframe. For the other load case, opposing loads were applied to the beam model near the right front tire and on the right front center suspension to simulate the effects of a left-hand turn on the chassis since nearly all races are run in a counterclockwise fashion. Results from this load case were used as a comparison of stiffness between the front and rear chassis.

To enable possible translational movement in the y-direction, Erwin applied boundary conditions with five degrees of freedom to four points along the main frame rails. To determine the stiffness of boundary elements at these same points, he used Algor's Internal Forces Calculator to determine the reaction force at each constraint. Then he loaded a laboratory test car in order to get the actual measured deflection. By dividing the reaction force by the actual deflection, Erwin determined the theoretical boundary element stiffness. After his first analysis run, Erwin found that the rear of the chassis was half as stiff as the front, a condition that was suspected to be contributing to an oversteering problem found in previous track tests.

Based on the findings of his initial analyses, Erwin modified the cross-sectional properties and placement of the beam elements to decrease deflection in the rear chassis. The structure of the chassis was further modified by eliminating an X-shaped brace in the upper rear chassis. This design modification was confirmed with track testing at the Atlanta Motor Speedway. As a result of the Algor analysis, Erwin was able to lower the center of gravity by 1/10-inch through structural modifications without significantly displacing the weight of the chassis.

Erwin found a correlation of over 94 percent between his analyses and physical testing. Differences were attributed to the presence of the suspension and rear end housing, which were not fully modeled. He plans to continue optimizing the stiffness of his chassis design while reducing its weight.

Despite his engineering efforts, Team Sabco met with rough luck at the 1999 Daytona 500, where both Joe Nemechek and Sterling Marlin were caught up in the same collision on lap 135.

The plant, which is a joint-venture limited partnership between BASF Corp. and FINA Inc., will convert naphtha and light hydrocarbons into ethylene and propylene, key raw materials in the manufacture of plastics, fibers, solvents, paints, and surfactants. A direct pipeline from the new cracker will carry the propylene and ethylene to the BASF plants in Freeport, Texas, and Geismar, La., for processing. The new plant is being built next to an existing FINA refinery in Port Arthur to optimize refinery and cracker feedstocks as well as by-product streams.

ABB Lummus Global began developing a 3-D model of the plant design shortly after winning the turnkey engineering, procurement, and construction contract in mid-1998. The contractor is using PlantView, the PASCE 3-D physical modeling program. The model provides a common database for several computer applications, and is updated and refined as detail is added. When construction is completed, the PlantView database will be delivered to BASF, which will run the plant for the joint venture. The 3-D model also furnishes data to PlantWalk, the PASCE tool for 3-D visualization and virtual walk-throughs.

Toolbox/MB will create complete assemblies in just four picks and includes components such as core pins, ejector pins, A and B plates, dowel pins, locating rings, and bushings. Built-in design tools help a user add ejector pins and support pillars.

Cimlogic is in Nashua, N.H.

The problem had surfaced in the field when service personnel were installing a replacement power supply in one of the company's huge memory testers. The bulky power supply must be rack-mounted in a frame that also holds large card cages filled with PC boards, fan trays, and heat exchangers. Replacing the power supply in such a crowded rack is a "blind" operation; the service person cannot see the insertion area. In about 15 percent of the cases, as the service person plugged in the power supply, the rear contact fingers did not align with the mating connector and would get bent under the insertion force. Each supply was worth $3,000, so damage was costly.

Teradyne engineers devised an inexpensive spacer that would mount between each finger of the power supply and prevent the fingers from bending under the insertion force. But while the spacer added stiffness, it also partially blocked the airflow exiting the power supply. This blockage could damage the 550-W power supply and disrupt the cooling pattern downstream.

Wind tunnel testing verified that the air temperature at various distances from the power supply exit fell within the allowable limits. Next, the engineers used Coolit to create a thermal simulation of the internal conditions. To solve the simulation problem, Coolit automatically divided the problem into a contiguous set of grid cells (finite volumes) and calculated its way from cell to cell. Temperature distribution patterns were color-coded to show the hot spots. Velocity vectors indicated the direction and speed of air movement through the volume. When the two graphics were overlaid, the interaction between airflow and temperature became apparent.

The redesign delivered better thermal performance. Apparently, the spacer increased air turbulence and, therefore, created a more thorough mixing of the air downstream. The validity of the simulation data was reinforced when downstream simulation results matched the actual experimental temperatures measured in the wind tunnel. Once verified, the design change was quickly incorporated into production. To date, 300 new systems have been built with this modification.

Pending regulatory approval, Rockwell Automation will buy the intellectual property and assets from Dynapro for the human interface programs sold under Rockwell Automation's Rockwell Software brand and for the Allen-Bradley PanelView "e" operator terminals and other control and communication products. Dynapro will continue to develop, manufacture, and market touch screen and industrial computer products under its own brand.

Dassault Systemes has announced agreements to make its CATIA Version 5 available on NEC Express, Dell Precision, Siemens Celsius, and Silicon Graphics Visual workstations, all of which run Windows NT. In a six-month pilot program, Toyota, the world's third-largest vehicle manufacturer, has successfully linked the SDRC Metaphase Enterprise product management software to ToyotaÕs proprietary CAD, bill-of-materials, and requirements/specifications applications. Toyota now plans to use Metaphase Enterprise for its main electronic data interchange system.

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