River beds, where flowing water meets silt, sand and gravel, are critical ecological zones. Yet how water flows in a river with a gravel bed is very different from the traditional model of a sandy river bed, according to ...
Environment
Oct 16, 2014
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For 60 years the world has believed that dolphins did not have enough muscle to propel them at high speed and that they were resorting to some fluid-flow trickery to pull off their impressive performance. But Frank Fish from ...
Plants & Animals
Jan 15, 2014
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(Phys.org) —A team of researchers in the U.S. has found that jellyfish are extremely efficient swimmers. In their paper published in Proceedings of the National Academy of Sciences, the team reports using a technique called ...
As of today, the Wikipedia entry for the hummingbird explains that the bird's flight generates in its wake a single trail of vortices that helps the bird hover. But after conducting experiments with hummingbirds in the lab, ...
General Physics
Feb 25, 2013
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(Phys.org)—Ever since the Wright brothers, engineers have been working to develop bigger and better flying machines that maximize lift while minimizing drag.
Engineering
Dec 13, 2012
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Pavlos Vlachos, associate professor of mechanical engineering at Virginia Tech, working with two engineers from Utah State University, has won the Lewis F. Moody Award for an outstanding original paper useful to the practice ...
Engineering
Feb 15, 2011
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A green laser flashed across the high-pressure spray that fuels a jet engine. Those flashes, some just 50 millionths of a second apart, froze the droplets for a camera to record and a computer to analyze.
Engineering
Dec 22, 2010
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(PhysOrg.com) -- "Smooth" and "quiet" are two words not usually associated with a helicopter ride, but NASA is working to change that. A full-size UH-60A Blackhawk helicopter rotor was the subject of tests the agency's Subsonic ...
Engineering
Jun 7, 2010
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Much more oil is spewing into the Gulf of Mexico from a sunken British Petroleum oil rig than official estimates show, experts warned Friday as BP executives stuck to their guns and even tried to play down the size of the ...
Environment
May 14, 2010
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(PhysOrg.com) -- Dead zones in critical waterways, accelerated loss of arable land and massive famines. They're all caused by the 24 billion tons of soil that are lost every year to erosion, a phenomenon that costs the world ...
Earth Sciences
Oct 12, 2009
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