EagleTribune.com, North Andover, MA

World/National News

May 12, 2013

Pinning down the physics of bubbles


So to describe the foam’s behavior, the researchers produced separate equations for the different aspects of foam dynamics. One set of equations governed how the walls of bubbles thin out and then break as liquid drains from their fragile skins.

Other equations focused on how liquid flows at the junctions between bubble membranes. Still more addressed how the spheres shuffle their positions within the foam as other bubbles burst, contorting to conserve surface area.

The pair also developed equations to describe the way a sunset would look when reflected in bubbles, its golden tones spread out into rippling hues like an oil slick.

When they were done writing their equations, they used them to create a video of a cluster of bubbles popping out of existence, one by one.

Separating out each layer of equations made the task slightly easier — though it still took five days for supercomputers at the Department of Energy’s National Energy Research Scientific Computing Center to churn through them and produce the simulation.

Taken together, the equations describe the dynamics of foam made up of hundreds of bubbles of various sizes, Saye and Sethian wrote in Science.

“It is just a first step along a road to understanding the kind of foams we find in industry, in chemical plants,” said Denis Weaire, a physicist with Trinity College in Ireland who was not involved in the work.

“Today the chemical engineer faced with designing such (a) plant must rely on extrapolation from experience, and guesswork,” Weaire said. “To do better we need realistic models. They could arise out of calculations like this.”

Text Only | Photo Reprints
Latest News
World/National News

Latest U.S. News
Obama: World Is Appalled by Murder of Journalist Pres. George W. Bush Takes Ice Bucket Challenge Changes Coming to No-Fly List Police: Ferguson More Peaceful Fire Crews Tame Yosemite Fire Raw: Police Weapon Drawn Near Protesters, Media Arrests Witnessed in Ferguson Charter Schools Alter Post-Katrina Landscape Texas Gov. Perry: Indictment 'a Political Act' US Officials: Video Shows American's Beheading Heavy Rains Flood Arizona Roads Video Shows Ferguson Cop Months Before Shooting US Trying to Verify Video of American's Killing FBI Director Addresses Ferguson Shooting in Utah Raw: Police at Scene of St. Louis Shooting Police: 2 Calif. Boys Planned School Shooting NOLA Police Chief Retires Amid Violent Crimes Lunch Bus Delivers Meals to Kids Out of School Water Bottles Recalled for Safety Researcher Testing On-Field Concussion Scanners
Latest World News
Israel, Militants Trade Fire After Talks Fail Raw: IDF Footage Said to Show Airstrikes Raw: Aftermath of Airstrike in Gaza Raw: Thousands March on Pakistani Parliament Raw: World's Oldest Man Lives in Japan Raw: Deadly Landslides in Japan Raw: Explosions in Gaza As Airstrikes Resume Today in History August 20 US Officials: Video Shows American's Beheading US Trying to Verify Video of American's Killing Rockets Fired From Gaza, in Breach of Ceasefire Raw: Japanese Military Live Fire Exercise Today in History August 19 Raw: Russian Aid Convoy Crosses Into Ukraine Raw: Building Collapse in South Africa, 9 Dead Assange Gets Cryptic About Leaving Embassy in UK Raw: Pope Francis Meets 'Comfort Women' Kurdish Peshmergas Retake Mosul Dam WikiLeaks Founder Says He'll Leave Embassy Soon Raw: Israel Destroys Killing Suspects' Homes
Photos of the Week