Developments to Watch
PUTTING A BIT LESS INDUSTRY INTO INDUSTRIAL BLADES
MERHDAD ZANGENEH WANTS to take the black art out of designing blades for pumps, compressors, and turbines. The researcher in University College London's mechanical engineering department says his superscript3-D software tool can cut design time from six months to a few days, while coming up with blades that preliminary tests indicate could be up to 10% more efficient.
Zangeneh uses inverse design. Instead of guessing at a good blade shape, and then testing its output, Zangeneh starts by specifying the output he wants. Then his computer program works backward to generate an efficient blade shape. The design concept has been around since the 1930s, but Zangeneh has moved the idea ahead by perfecting a computer program to carry it out.
So far, Zangeneh's program works for machines in which a fluid or gas is sucked into a blade and flung outward at a 90-degree angle as the blade spins. But he believes that within three years his technique could be extended to design axial compressors, such as those in jet engines, in which air or liquid flows through blades without changing direction.
Ebara Corp., the world's largest pumpmaker, is Zangeneh's biggest supporter. The Japanese company is testing prototypes and expects to begin production next year. Hiroyuki Kato, general manager of Ebara's Haneda Plant engineering development department, says that when it comes to blade design, "Zangeneh's technique...has the possibility to become the law."EDITED BY PETER COY By Heidi DawleyReturn to top
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FOR DIABETICS, A HEALTHY CANDY BAR
MILLIONS OF AMERICANS have been diagnosed with type II diabetes--meaning they don't need daily insulin injections but must exercise, monitor their diet, and give up sweets. Even small quantities of confections can cause their blood sugar levels to soar dangerously.
But someday their diets might include a special candy bar. Doctors at the University of Maryland at Baltimore have just completed a yearlong study of D-tagatose, a sugar found in yogurt and some cheeses. Reporting at a June meeting of the American Diabetes Assn., they described how eight mildly diabetic individuals and eight control subjects were given D-tagatose prior to getting a standard dose of glucose used in diabetes testing. The substance blunted the peak in blood sugar that normally occurs after subjects receive glucose. A second year of tests will help determine possible side effects.
D-tagatose was developed in the late '80s as a nonfat sweetener by Bio-spherics Inc. of Beltsville, Md., which holds patents on its use. During animal tests, researchers noticed its medicinal effects. D-tagatose has roughly the same sweetness as sucrose and will soon be marketed in Australia as a food ingredient, says Lee Zehner, Biospherics' vice-president for science services. U.S. trials could take another two to five years.EDITED BY PETER COY By Neil GrossReturn to top
A BETTER-TEMPERED CLAVIER
ALTHOUGH IT HAS IGNITED THE COMPOSITIONAL GENIUS of Beethoven, Chopin, and countless others, the piano has a terrible flaw: It is slightly out of tune. Singers, violinists, and horn players can raise or lower notes to play in tune in any key--but not pianists. They are stuck with the 300-year-old "equal temperament" tuning system that lets them play in all keys, but at the cost of being out of tune in each.
A Vancouver (B.C.) software company says it has solved that problem in electronic keyboards. Justonic Tuning Inc. uses computer analysis to recognize pitches and retune them--as the keyboard is being played--to produce pure harmony. "Under each note, there is a whole range of frequencies that can sound," explains Justonic President Rex Weyler.
The company has also joined with Virtual DSP Corp. of Everett, Wash., to devise a similar system that will retune electric guitars. The software, which will become available in the fall, requires that keyboard players and guitarists connect to a personal computer. It could eventually be reduced to a built-in chip.EDITED BY PETER COY By Paul RaeburnReturn to top