SCIENCE IN THE NEWS DAILY
Falling Stout Bubbles Explained
from BBC News Online
Irish mathematicians may have solved the mystery of why bubbles in stout beers such as Guinness sink: it may simply be down to the glass. Simulations suggest an upward flow at the glass's centre and a downward flow at its edges in which the liquid carried the bubbles down with it.
But the reasons behind this flow pattern remained a mystery. Now a study on the Arxiv server reports simulations and experiments showing the standard glass' shape is responsible.
Many stout beers contain nitrogen as well as the carbon dioxide that is present in all beers. Because nitrogen is less likely to dissolve in liquid, that results in smaller and longer-lasting bubbles. But it is the sinking bubble that has confounded physicists and mathematicians alike for decades.
Connect With Us:
VIDEO: The Promise and Peril of Drones
The automation of tasks at work and at home is just around the corner, including driving cars, piloting planes, delivering packages, and transporting weapons. Unmanned aerial vehicles are rapidly evolving to meet both society’s and the military’s needs in automation and better efficiency.
During her time as one of the first female fighter pilots in the US Navy, Dr. Missy Cummings observed that computers could take off and land a plane more precisely than humans. Because of this breakthrough and her fascination with this growing technology, she began human–drone interaction research.
To view all multimedia content, click "Latest Multimedia."
Receive notification when new content is posted from the entire website, or choose from the customized feeds available.