0

IN THIS ISSUE


Select Articles

Mechanical Engineering. 2009;131(12):24-28. doi:10.1115/1.2009-DEC-1.
FREE TO VIEW

This article focuses on benefits of the electric meters capable of sharing real-time usage data with the company and customers alike. Creating the smart grid on a national scale will be perhaps the biggest change to the electrical system since the rural electrification effort of the 1930s. Companies are trying to get a more reliable energy system through, for example, outage management systems, rebalancing loads, and getting help with rebalancing through consumers controlling their usage. To provide real-time or near-real time information, which is needed for consumers to monitor and control their usage, the electric meters must communicate with each other frequently. Sensing and monitoring devices at customer premises that let customers control their electric use are explicit elements of smart grids The future smart grid, Smart Grid 2.0, is next-generation, interactive, self-healing, distributed everywhere, and has an innate capability to reach every device.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(12):29-31. doi:10.1115/1.2009-DEC-2.
FREE TO VIEW

This study highlights that wind and geothermal power are now a better investment than coal. Biofuels startups are tapping millions in venture capital funds; and techniques for drawing power from wind, ocean, and solar energy have also seen an influx of R&D dollars. According to Schilling, both wind and geothermal power are poised to become more economical than fossil fuel, needing just a relatively small infusion of additional capital. When people teach innovation and strategy in economics, the S-curve is given. Although electricity-generating technologies are subject to different economic forces than, say, disk drives or semiconductors, Schilling says the S-curve model should apply to them as well. When Schillings fit the performance versus investment data on an S-curve, the technology appeared just at the beginning of a long period of improvement. In the near term, wind and geothermal power have the best potential for performance growth, according to Schilling’s analysis, and make the best sense for additional R&D.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(12):32-37. doi:10.1115/1.2009-DEC-3.
FREE TO VIEW

This article discusses the real-world practicality of nuclear power. Neither reactors nor casks of spent fuel have the capability of going “prompt critical” like a bomb. The laws of nature prohibit it and engineers must make clear that facts of nature are not matters of opinion. The Chernobyl reactor, which failed so spectacularly in Ukraine in 1986, became for many a symbol of the dangers represented by nuclear reactors. But that is not warranted; such an accident is simply impossible for the kind of commercial reactors now being planned or built. From a public safety standpoint, the most important feature of our current reactors is that, after any event that ruptures the reactor coolant system, a large amount of water and steam would be violently swirling around inside the containment structure, even if containment structure has been ruptured. In the emerging context of realistically reexamining many long-held assumptions, engineers will find opportunities to drastically improve the way nuclear power plants are built and operated.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(12):38-42. doi:10.1115/1.2009-DEC-4.
FREE TO VIEW

This article discusses gas turbine efficiency, which is an essential but often unappreciated aspect of turbomachine design pitch. To an engineer, the pitch of a turbo machinery blade is the angle at a representative blade cross-section between the blade chord line and the plane of the blade’s rotation. An axial flow gas turbine consists of many rows of rotating blades, interspersed with rows of stationary airfoils, called vanes or stators. The gas turbine compressor (whose first row of rotating blades in a jet engine may be a fan) draws in air, which after passing through a combustor to add energy to the air flow, powers the turbine which drives the compressor. Most modern commercial jet engines are turbofan, with a front mounted fan, whose size is indicated by the bypass ratio. During the 1990s, jet engine companies developed and tested variable pitch turbofans, with cycle studies showing between 6 and 14% fuel savings. If fuel savings could spread through the airline industry, changing the pitch could lead to air carriers singing a happier tune.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(12):44-46. doi:10.1115/1.2009-DEC-5.
FREE TO VIEW

This paper highlights managing engineering documents electronically—that is, via a computer system on which users share files—enables all engineers to be on the same page, literally. But benefits extend far beyond what is called as version control. Those engineering firms that need to keep documents to comply with regulatory requirements find the software to be vital. Digital management prevents too many cooks (or engineers) from spoiling the design soup by ensuring only one person at a time gets to make changes to a drawing or document. Workflow management means incipient designs can pass between pertinent mechanical engineers, analysts, and manufacturing engineers at the proper time in the design cycle. The experience of the engineers at AWB Engineers, a consulting firm in Salisbury, Md., is pretty typical of the benefits of managing documents electronically. While the engineers there were doing their best to control the overwhelming number of documents, CAD files, change orders, and the like that flowed through the company every day, managers still ran into trouble.

Commentary by Dr. Valentin Fuster

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In