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Mechanical Engineering. 1999;121(01):46-50. doi:10.1115/1.1999-JAN-1.
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This article reviews the copper cables in Detroit Edison’s Frisbie Station to be retrofit in mid-2000 with high-temperature superconductor (HTS) cables to support a major urban redevelopment project in downtown Detroit. American Superconductor’s partner, Pirelli, is participating in this project. The three HTS cables, weighing 250 pounds, will carry 100 megawatts of power, a job that nine copper cables, with a total weight of 18,000 pounds, are doing. In Germany, Siemens AG has invested hundreds of millions of dollars into researching HTS, because the capability can bring improvements across the German conglomerate’s businesses, from power to transportation to electronic devices. The principal commercial US players are American Superconductor, 3M, and Intermagnetics General. Each has organized efforts to develop commercial processes for manufacturing HTS tape based on coated conductors.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 1999;121(01):52-56. doi:10.1115/1.1999-JAN-2.
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This article discusses that a probabilistic study showed that the use of double-hulled shuttle tankers could reduce the probability of spillage resulting from collisions, contact with non-ship objects, and groundings by 75 percent. American petroleum companies are already using double-hulled tankers. The efficacy of double-hulled vessels in preventing environmental threats was borne out in October 1997 by Conoco Inc.’s tanker Guardian. Conoco, based in Houston, has operated a 100 percent double-hulled U.S. tanker fleet since August 1998. Indeed, the company decided to build only double-hulled tankers months before Congress passed OPA 1990. Two new craft will join Conoco’s flotilla of four twin-hulled vessels in 1999. Conoco engineers met a number of challenges when they embarked on building a double-hulled fleet. Double-hulled vessels are inherently more expensive than single-hulled vessels. Maritrans Operating Partners LP, a wholly owned subsidiary of Maritrans Inc. in Philadelphia, operator and owner of one of the nation’s largest fleets of oil tankers, tugboats, and oceangoing petroleum tank barges, found a way to reduce those costs, which may serve as a model for other shipping firms. The 65-year-old company converted a two-decade-old single-hulled tank barge into a double-hulled vessel.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 1999;121(01):58-61. doi:10.1115/1.1999-JAN-3.
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This article focuses on how manufacturers have pushed the limits of plastic, glass, and other materials by turning them into sturdy foams. Materials created by mixing a solid with minute spheres of glass ceramic, or polymer are finding an increasing range of uses in industrial and high-tech applications. Microspheres, both solid and hollow, have wide commercial uses. Polymer microspheres appear in the medical, pharmaceutical, and cosmetics industries, for applications ranging from blood circulation tracers in research, to time-release capsules in medicines, to facial oil absorbers in makeup. At Northeastern University in Boston, Teiichi Ando is producing metallic microspheres to investigate various metallurgical phenomena. When the spheres are subjected to extremely high cooling rates, they can form as metallic glasses, supercooled metals that have not crystallized. The resulting spheres are free of grain boundaries and other flaws. Syntactic foam ingots of various alloys have been produced using moderate pressure infiltration of silica-alumina spheres.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 1999;121(01):62-63. doi:10.1115/1.1999-JAN-4.
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This article highlights that engineers at TU Electric’s largest plant tested the flow rate of the water circulating system, which helped them to reduce its pumping power consumption by 9 percent. The plant hired a company to run a calibrated turbine meter thro ugh the pipes. The total generating capacity at TU Electric’s plants tops 20 million kilowatts. TU Electric’s Martin Lake plant, in Rusk County, Texas, has three units, each with a capacity of 750 megawatts, which makes it the largest-capacity plant in the utility’s system. The first field measurements at the Martin Lake plant were conducted for TU Electric by Encor–America Technologies 1nc. Encor subcontracted with Flow Simulation Services (FSS) to perform a CFD simulation. CFD involves the solution of the governing equations for fluid flow at thousands of discrete points on a computational grid.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 1999;121(01):64-66. doi:10.1115/1.1999-JAN-5.
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This article reviews how computational fluid dynamics (CFD) analysis provides an enhanced understanding of a low-emission combustion system. When AlliedSignal Engines in Phoenix wanted its ASE40 industrial gas turbine to meet tough new standards for nitrogen oxide emissions, the company decided to try a design that injected water into the combustion zone so the system would burn cooler. AlliedSignal combined full-scale engine tests and computer models to study the effect of water injection on the ASE40. CFD provided detailed flow field information not available from engine tests. This information allowed engineers to verify the effectiveness of the numerous design changes made in axial air swirlers, mixing jets, and cooling flows. Work is also in progress on a dual-fuel system with water injection, using the same gas/water manifold and combustor. Oil fuel will be introduced through the original water circuit, with water being introduced into the gas side. This system will be distributed for the European market by AlliedSignal’s partner, Motoren-und Turbinen-Union (MTU) of Friedrichshafen, Germany.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 1999;121(01):68-69. doi:10.1115/1.1999-JAN-6.
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This article discusses servo motion systems, which are motion control systems that combine hardware and software, have innumerable applications in compact modules. Some motion controllers operate on multiple platforms and buses, with units providing analog output to a conventional amplifier, as well as units that provide current control and direct pulse width modulation (PWM) output for as many as 32 motors simultaneously. There are amplifiers that still require potentiometers to be adjusted for the digital drives’ position, velocity, and current control. All major value-adding components of motion control systems will soon have to comply with the demands for faster controllers with high-speed multi axis capabilities supplying commands in multitasking applications.

Commentary by Dr. Valentin Fuster

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