Design for enviroment process targets automaking
How can engineers assess the environmental impact of their designs for a complex product such as a car? Since 1989, Sweden's Volvo Corp. has been developing a tool to answer that question. It is a system called Environmental Priority Strategies in Product Design (EPS). The system is described in a new book The Industrial Green Game, put together by the National Academy of Engineering. The key element of EPS is an environmental index that enables the adverse effects of emissions and the use of various natural resources to be quantified and subjected to sensitivity analysis. Different factors can be weighed together to produce a single value describing the total environmental load. Volvo has created environmental indices for pure materials, as well as processes or parts of processes required by different design options. The company has tested EPS in its Environmental Concept Car. To order the publication, call the National Academy Press at (800) 624-6242. The single-copy price is $38.95, including shipping and handling.
Diesels get added attention in 'supercar' project
The federal administration is leaning more and more toward the diesel engine to power the early version of its envisioned "supercar." Under the Partnership for a New Generation of Vehicles (PNGV) program, the government has launched a fresh plan for intensified diesel research. The aim: to produce the world's cleanest diesel engines. Compared with current diesels, the new engines would emit 80% less NOX and 50% fewer particulates. The plan calls for three major areas of research. Under engine technology, emphasis will be on the possibility of replacing conventional diesel fuel. Combustion research will examine advanced fuel injection, engine controls and sensors, and combined combustion cycles. The third area will concentrate on after treatments to further reduce tailpipe emissions, using new catalysts and traps. The choice of technologies for the first round of PNGV vehicles--the so-called "downselect"--will come at the end of this year.
Simulation technique predicts precision of machine tools
A powerful, fast, and versatile simulation technique provides designers of machine tools with a means of immediate feedback. For alternate combinations of components, they can evaluate performance tradeoffs and then optimize specifications for building and assembly. The system is called Machining Variation Analysis (MVA). A team from the National Institute of Science and Technology, the Massachusetts Institute of Technology, and the Landis Division of Western Atlas, a Pennsylvania maker of grinding equipment, developed MVA. The software tool exploits four powerful mathematical methods to estimate--in minutes instead of days--machining errors in the dimensions and geometry of parts. For more information, contact Johannes Soons at (301) 975-6474 or e-mail [email protected].
Technologies for light planes advance on array of fronts
Can light airplanes be made as easy to operate as cars? Yes, say leaders of the Advanced General Aviation Transport Experiment (AGATE) Alliance. The government and the U.S. general aviation industry formed and began funding the AGATE project three years ago, hoping to make light planes safer and simpler to operate. Recently, AGATE partners have reported major strides toward their goal. One partner successfully controlled an air-cooled engine of a light plane with a single electronic lever during flight. Among other AGATE advances: development of a digital data link radio using affordable technologies for retrofit, as well as for use in future general aviation craft; and a fixed-pitch propeller made of new composite materials that enable it to perform like a variable-pitch propeller. In yet another AGATE program, a NASA contractor purposely crashed a small airplane designed to protect occupants against fatal injuries using airbags and energy-absorbing composite structures. All crash dummies on board "survived"--a first for general aviation crash tests.
Launch engine for X-34 passes critical series of tests
A rocket engine that could power the next generation of space launch vehicles has successfully completed key ground tests by NASA technicians. The Fastrac engine is only the second engine developed in the U.S. in the past 25 years. It will be the primary propulsion for the X-34 technology demonstration vehicle scheduled to begin flight tests late in 1998. Tests at the Marshall Space Flight Center in Huntsville, AL, evaluated Fastrac's thrust chamber assembly at high pressure almost identical to flight conditions. The primary combustion of propellants--a mixture of liquid oxygen and kerosene--occurs in the thrust chamber assembly. As the engine heats, the chamber is cooled by charring or scorching a chamber liner that decomposes to prevent excessive heat buildup. The thrust chamber assembly performed as designed.