(Press-News.org) Wine drinkers know that swirling a good vintage around in a glass aerates the wine and releases its bouquet. Just how the process – known as "orbital shaking" – works, however, has been something of a mystery.
Fluid dynamicists have long observed that orbital shaking generates a wave that propagates around the inner edge of the glass, churning the liquid as it travels. "The formation of this wave has probably been known since the introduction of glass or any other kind of cylindrical bowl, but what has been lacking is a description of the physics related to the mixing and oxygenation," says Mohamed Farhat, senior scientist at the Ecole Polytechnique Federale de Lausanne in Switzerland.
To figure out how the mixing occurs, Farhat and his colleagues generated such waves in clear cylinders and used state-of-the-art instrumentation to track the motion of traveling waves and measure the liquid velocity.
The researchers found that "as the wave propagates along the glass wall, the liquid is displaced back and forth from bottom to top and from the center to the periphery," Farhat explains. "This pumping mechanism, induced by the wave, is more pronounced near the free surface and close to the wall, which enhances the mixing." The research team also discovered that, "for a given glass shape, the mixing and oxygenation may be optimized with an appropriate choice of shaking diameter and rotation speed," he says.
"The intuitive and efficient motion of wine swirling has inspired engineers in the field of biopharmaceuticals," Farhat says, where cell cultures can be placed in large cylindrical containers – or bioreactors – and "shaken" in a manner similar to the aeration of a glass of wine. The new work, he says, demonstrates that "such bioreactors offer better mixing and oxygenation over existing stirred tanks, provided that operating parameters are carefully optimized. Moreover, the gentle nature of orbital shaking also ensures a better viability and growth rate of the cells at reduced cost."
Martino Reclari, a Ph.D. student and a member of the Swiss team, will present the findings in a talk at the American Physical Society's Division of Fluid Dynamics Meeting, which will take place Nov. 20-22, 2011, at the Baltimore Convention Center in the historic waterfront district of Baltimore, Maryland.
###
The talk, "'Oenodynamic': hydrodynamics of wine swirling," is at 12:01 p.m. on Monday, Nov. 21, in Room 318. Abstract: http://absimage.aps.org/image/MWS_DFD11-2011-002246.pdf
MORE MEETING INFORMATION
The 64th Annual DFD Meeting is hosted by the Johns Hopkins University, the University of Maryland, the University of Delaware and the George Washington University. Howard University and the U.S. Naval Academy are also participating in the organization of the meeting. It will be held at the Baltimore Convention Center, located in downtown Baltimore, Md. All meeting information, including directions to the Convention Center, is at: http://www.dfd2011.jhu.edu/index.html
USEFUL LINKS
Main Meeting Web Site: http://www.dfd2011.jhu.edu/index.html
Search Abstracts: http://meeting.aps.org/Meeting/DFD11/Content/2194
Directions and Maps: http://www.dfd2011.jhu.edu/venuemaps.html
PRESS REGISTRATION
Credentialed full-time journalists and professional freelance journalists working on assignment for major publications or media outlets are invited to attend the conference free of charge. If you are a reporter and would like to attend, please contact Charles Blue (cblue@aip.org, 301-209-3091).
SUPPORT DESK FOR REPORTERS
A media-support desk will be located in the exhibit area. Press announcements and other news will be available in the Virtual Press Room (see below).
VIRTUAL PRESS ROOM
The APS Division of Fluid Dynamics Virtual Press Room features news releases, graphics, videos, and other information to aid in covering the meeting on site and remotely. See: http://www.aps.org/units/dfd/pressroom/index.cfm
END
KINGSTON, R.I. – November 21, 2011 – A nest containing the fossilized remains of 15 juvenile Protoceratops andrewsi dinosaurs from Mongolia has been described by a University of Rhode Island paleontologist, revealing new information about postnatal development and parental care. It is the first nest of this genus ever found and the first indication that Protoceratops juveniles remained in the nest for an extended period.
The findings were reported in the most recent issue of the Journal of Paleontology.
David Fastovsky, URI professor of geosciences, said the bowl-shaped ...
In the early '90s, a Department of Defense engineer at NASA assigned to work on the now defunct Super Conducting Super Collider project was sidetracked with a personal mission that had nothing to do with subatomic particles or electromagnetic fields. Instead, after federal budget cuts ended the project, Ron Green assigned himself an entirely new operation: hatching up the country's perfect breakfast, brunch and lunch restaurant concept.
Mission accomplished. Today, Another Broken Egg Cafe cracks more than 900,000 eggs a week at its 18 bustling locations in seven states, ...
Alexandria, VA – Is the United States entering its "Lost Decade"? A crunch on natural resources coupled with a crippling economic crisis and an aging workforce threaten to hurl us into a decade—or more—of grudgingly slow development akin to that of the Japanese after their own real estate bust a few decades ago. Will the United States learn from past mistakes in order to reconcile economic growth with environmental safety? In the December issue of EARTH Magazine, learn how the facts and the fallacies measure up to the increasing challenges facing the United States in 2012 ...
INDIANAPOLIS — The scoring system government agencies use to rate nursing home quality does not provide an adequate evaluation because they do not take into account the degree of cognitive impairment of their patient populations and whether facilities include a specialized dementia unit according to a new study.
Focusing on statistics from Minnesota, researchers from Indiana University School of Medicine and the Regenstrief Institute report on the inadequacy of quality of care indicators for nursing home residents with behavioral and psychological systems related to dementia ...
Le Meridien Amman, a hotel dedicated to offering a chic experience, has recently hosted a "Culinary Wine Tasting" event, in the stylish setting of 282 Steaks and Lounge restaurant, in cooperation with Yousef M. Haddad & Partners Company and Kaylani Food Center.
Mr. Frederico Raviola from the Fontanafredda winery in Italy, the first in Piedmont to be awarded the official "Integrated Farm Management" Certification, briefed the audience on the different types of wines, in an informal market atmosphere. The invitees, amongst them many ambassadors, ...
Certain patients with inflammatory bowel disease (IBD) may have an increased risk of skin cancer, which is intensified by the use of immunosuppressant medications , according to two new studies in Gastroenterology, the official journal of the American Gastroenterological Association. Immunosuppressants are commonly used in the treatment of IBD.
In the first study, researchers found that both past and present exposure to thiopurines (a widely used class of immunosuppressants) significantly increased the risk of nonmelanoma skin cancer (NMSC) in patients with IBD, even ...
Rockville, Md. – Whether comparing a man and a woman or a parent and a baby, we can still see when two people of different age or sex are genetically related. How do we know that people are part of a family? Findings from a new study published in the Journal of Vision increases our understanding of the brain's ability to see through these underlying variations in facial structure.
"Being able to see the family resemblance between faces that have some underlying difference, such as the difference between male and female faces, is an ability that is not well understood ...
Kearney A. Snyder Funeral Home, serving families since 1940, continued to live up to their reputation of unmatched attention to detail by launching their new website to offer the families of the Lancaster area easy accessibility to resources and information. http://www.KearneyASnyderFuneralHome.com
Kearney A. Snyder Funeral Home have just launched their new website to provide families of the Lancaster community with education, support and resources during the loss of a loved one.
Jeremy DeBord, representing the fourth generation of the Kearney A. Snyder Funeral Home, ...
Field emission devices, which produce a steady stream of electrons, have a host of consumer, industrial, and research applications. Recent designs based on nanotubes and other nanomaterials embedded in plastics show initial promise, but have a number of drawbacks that hinder their wide-scale application. The embedded nanotubes, which serve as the source for the electrons, also enable the normally inert plastic to conduct electricity. This has the desired effect of producing a versatile and easily manufactured field emission device. But since plastics are, by nature, poor ...
MONTRÉAL, November 21, 2011 – Natural selection has played a role in the development of the many skins patterns of the tiny Ranitomeya imitator poison dart frog, according to a study that will be published in an upcoming edition of American Naturalist by University of Montreal biologist Mathieu Chouteau. The researcher's methodology was rather unusual: on three occasions over three days, at two different sites, Chouteau investigated the number of attacks that had been made on fake frogs, by counting how many times that had been pecked. Those that were attacked the least ...
