Arrows show direction of hydrogen flows through fuel flow and oxidant field plates and through PEM.

DaimlerChrysler Corp.'s support showed especially when it unveiled in Washington the NECAR (new electric car) 4 with Ballard's latest fuel cell technology. The car has "zero emissions"—as the federal regulations go—and is said to show a 40 percent increase in fuel cell power and up to three times the range of a battery-powered vehicle.

The NECAR 4 is based on a Mercedes-Benz A-class compact car and reaches speeds of 90 mph, compared with a top speed of 68 mph for its technological predecessor, NECAR 2. It can travel nearly 280 miles before refueling. For more space, engineers have been able to mount the complete fuel cell system in the vehicle floor for the first time.

DaimlerChrysler plans to have fuel cell vehicles in limited production by 2004. The company will invest more than $1.4 billion in fuel cell technology development by the time the first fuel cell vehicles come to market.

Juergen E. Schrempp, co-chairman of DaimlerChrysler, said, "Today, we declare the race to demonstrate the technical viability of fuel cell vehicles over. Now, we begin the race to make them affordable." The NECAR 4 is powered by liquid hydrogen stored in a cryogenic cylinder at the rear of the vehicle. The fuel is processed by the Ballard PEM cell, inside which a platinum-coated membrane separates hydrogen into protons and electrons, and combines them with oxygen in the air to form water. This surplus and deficit of electrons and protons creates positive and negative terminals that, when connected, produce electricity, which in turn powers the vehicle.

A Fakespace technician demonstrates how a fluid dynamics simulation created at Los Alamos National Laboratory can be displayed on the Immersive WorkBench. Composite image courtesy of Fakespace Inc. and Los Alamos National Laboratory.

Fakespace is drawing on its experience developing interactive visualization solutions for industry, government, and research institutions to build an 8 x 15-foot rear-projection video wall and a 7.5-foot diagonal front-projection display system for the Los Alamos project. Both displays will be equipped with state-of-the-art digital light valve solid-state projectors made by Electrohome Ltd. in Kitchener, Ontario. These projectors are designed to cast sharp images from high-resolution computers, workstations, and video sources.

The rear-projection flat display wall will contain six independent 4 x 5-foot screens and six projectors to support the display of a single 1,280 x 1,024 pixel-per-inch resolution image across the screens. This display will provide a total resolution of 3,840 x 3,072 pixels, or nearly 12 million pixels in all. The display system will work in conjunction with two Immersive WorkBench virtual model displays Fakespace installed at Los Alamos under a separate contract in October 1998. Researchers use the WorkBenches to view and manipulate three-dimensional, computer-generated models in real time, so that they appear to have a very real presence in space when viewed through stereoscopic shutter glasses. Fakespace Pinch gloves enable scientists to interact with the WorkBench images.

Using design analysis software, DEKA reduced the overall time to market for a medical stent by approximately four months.

The task fell to Larry Gray and Michael Martin, mechanical engineers at DEKA. The redesign posed the challenge of determining the physical requirements of the stent. Although they knew roughly what the blood fluctuation was, they needed to determine the strength required to keep the blood passage open. Doctors wanted the stent to be soft and flexible, so it could be maneuvered into place easily, yet stiff when expanded to keep the artery open. Also, the new design had to use the same material (316 stainless steel) and manufacturing process as the old one, which was FDA approved.

The stent struts, which average 0.007-inch wide, are cut with lasers that are accurate to ± 0.003-inch. Because of microscopic geometric variations, using physical prototypes to test was not an option. Instead, Multiphysics design software from ANSYS Inc. of Canonsburg, Pa., was used to model the extremes of the material and loading conditions.

By conducting material and nonlinear analyses, Gray and Martin developed a new stent that took advantage of the elasticity of the material, which has an elongation (the amount it can be stretched past yield without breaking) of about 60 percent. DEKA was also able to pinpoint and minimize stress concentrations on the new design.

Gray and Martin used the software to help design the stent to withstand millions of cycles (about 10 years under normal body conditions). The analysis showed that the design was well below the endurance limit of the material. One complete load cycle was modeled using multiple load steps. Using the results of the load steps, the design margin was calculated with classical fatigue equations.

With the new, proposed stent designs, DEKA's customer made sample stents to put through fatigue tests, examining every speciman under an electron microscope. The customer performed the required FDA test cycles, which took just over four months, simulating cardiovascu- lar pounding on the test vents. The ANSYS software was used to verify the test results and provide additional proof that the stent would satisfy FDA requirements.

Superfort conveyor belts carry gypsum laden with sulfur from brown coal that is burned in five Czech power plants.

The Czechs burn locally available brown coal, which is high in sulfur that must be removed by desulfurization equipment to reduce pollution. The Czech power industry uses large quantities of gypsum to fix the sulfur so that it can be discharged to conveyor belts for reprocessing elsewhere.

The sulfur-laden gypsum discharged from the power plants is heated to 80°C. It is corrosive and has a tendency to stick to rubber conveyors. In addition, the scrapers fitted to the conveyors to remove the gypsum will abrade belts if the scrapers are set too tight.

The five Superfort conveyors delivered to the Czech power plants over the past few months are constructed of extra-abrasion-resistant polyester and nylon fabric plies that are bonded together by layers of rubber. This configuration makes the belts sufficient- ly elastic to absorb shock loads and minimizes stretching. The Dunlop-Enerka belts also resist moisture, oil, grease, and fire.

The new Palmetto Interstate Pipe-line has a planned initial capacity of 200 million to 300 million cubic feet per day and will be expanded to accommodate future growth. CP&L plans to subscribe to a substantial portion of the Palmetto Pipeline capacity to fuel new electric generation being developed for its customers in the Carolinas. The remainder will be used to increase the region's natural gas availability.

Lasers at the Lockheed Martin Tactical Aircraft Systems plant in Fort Worth, Texas, craft a small stainless steel part.

The startup in Texas comes 18 months after Sandia National Laboratory formed a consortium within a cooperative research and development agreement. These arrangements, known as CRADAs, are the official contracts set up when government and industry embark on joint research. Contributors include Laser Fare Inc., the Providence, R.I., laser sintering specialty firm, and Allied-Signal Corp., the aerospace and materials giant in Morristown, N.J.

Brian Rosenberger, the team leader for the new laser engineered net shape process, said the technology allows manufacturers "to do in two weeks what now takes many months" and "make one part out of what takes hundreds of pieces using conventional technology." He added that moving the research focal point from Sandia to Lockheed Martin hastens the ability to make "real parts for real airplanes."

The authors, Ted McKenna and Ray Oliverson, work for HSB Reliability Technologies, a Hartford Steam Boiler division in Texas. McKenna is senior project manager, and Oliverson the executive vice president.

They write in their preface that, in 25 years of working with clients, "We have never failed to be puzzled at the varied words and definitions people use to denote key elements of this major area of business."

Their response is Glossary of Reliability and Maintenance Terms, which, according to the cover, has more than 1,000 terms and definitions. The lexicon is 139 pages, starting with "ABC classification" (the "classification of a group of items in decreasing order of annual dollar volume or other criteria") and ending with "zero-based budgeting."

McKenna and Oliverson's book sorts out various kinds of maintenance—for instance, preventable, proactive, and reactive—and the writers throw in a plug for an HSB proprietary term, "World Class Maintenance." One term they single out in their preface as a particu-lar source of confusion is "predictive maintenance," which they point out involves the use of sensors and other devices to monitor equipment in operation, but only becomes truly predictive when the data is used to anticipate failures before they happen.

The Glossary is distributed by HSB Reliability Technologies of Kingwood, Texas.

Consolidated Papers Inc. of Wisconsin Rapids, Wis., has begun investing $166 million in more than 30 major capital improvement projects. Included are the installation of a second debarking system at the company's Biron, Wis., facility and the construction of a peroxide bleach plant to replace a pulp bleaching plant at Consolidated Paper's Wisconsin River division in Whiting, Wis.

Fiat SpA of Milan and the Turin Politecnico will offer Italy's first degree program in automotive engineering at the Lingotto complex being built on the Politecnico campus. Classes will begin later this year for one of the few college-level programs in the world devoted exclusively to teaching and researching automotive design and manufacturing.

DTE Energy Co. of Detroit will be recycling pole-top and pad-mounted electrical transformers for clients, including Detroit Edison, its principal operating subsidiary. Transformers either will be refurbished and returned to service, or disassembled and sold to scrap metal dealers.

The potentially huge market represented by more than 400,000 computer- numerical-controlled machine tools in Germany led Manufacturing Data Systems Inc. of Ann Arbor, Mich., to open an office in Frankfurt. Half of the German CNC machines are at least 10 years old, and are prime targets for MDSI's OpenCNC, a software-based rather than hardware-based computer-numerical control.

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