Printer Friendly
The Free Library
5,665,934 articles and books
Member login
User name  
Password 
 
Join us Forgot password?

Dial-a-splash: thin air quells liquid splatter.


In a classic image of high-speed photography, a drop of milk landing on a surface explodes into an ornate or·nate  
adj.
1. Elaborately, heavily, and often excessively ornamented.

2. Flashy, showy, or florid in style or manner; flowery.
 crown with beads of fluid leaping from its rim. Now, a study of other splashes finds that the air in which such bursts unfold unfold - inline  is a previously overlooked actor in that performance.

"I don't think anyone ever thought poor little old air could do anything to the splash," says physicist Sidney R. Nagel, who led the investigation. Yet he, Lei Xu, and Wendy W. Zhang, all of the University of Chicago, have discovered that even modestly reducing the air pressure completely quells the rococo exuberance of crashing drops.

"Flabbergasting," comments Detlef Lohse of the University of Twente (body, education) University of Twente - A university in the east of The Netherlands for technical and social sciences. It was founded in 1961, making it one of the youngest universities in The Netherlands.  in Enschede, the Netherlands.

Nagel, Xu, and Zhang made their unexpected observations while releasing alcohol drops onto glass slides in a sealed chamber with adjustable air pressure. To monitor the impacts, the team filmed them at 47,000 video frames per second.

The experimenters also found that replacing air with lighter gases, such as helium helium (hē`lēəm), gaseous chemical element; symbol He; at. no. 2; at. wt. 4.0026; m.p. below −272°C; at 26 atmospheres pressure; b.p. −268.934°C; at 1 atmosphere pressure; density 0. , diminished splashing and that heavier gases, such as krypton krypton (krĭp`tŏn) [Gr.,=hidden], gaseous chemical element; symbol Kr; at. no. 36; at. wt. 83.80; m.p. −156.6°C;; b.p. −152.3°C;; density 3.73 grams per liter at STP; valence usually 0. , enhanced it.

To explain their results, the Chicago researchers posit that the leading edge of a fallen, squashed drop rushes outward, compressing com·press  
tr.v. com·pressed, com·press·ing, com·press·es
1. To press together: compressed her lips.

2. To make more compact by or as if by pressing.

3.
 a thin layer of gas next to the glass surface. At normal pressure, as the gas resists this compression, it forces up the film's edge, which then breaks up. The result: a splash.

But at reduced pressures--or if the gas is light--the compressed gas resists less vigorously, generating a weaker splash or none at all. The splash is "very tunable," Xu says.

The team details its findings in a report on the Internet site called ArXiv, where physicists Below is a list of famous physicists. Many of these from the 20th and 21st centuries are found on the list of recipients of the Nobel Prize in physics. A
  • Ernst Karl Abbe — Germany (1840–1905)
  • Derek Abbott — Australia (1960- )
 often post new results (www.arxiv.org/abs/physics/0501149).

Splashing occurs, for better or worse, in many industrial processes, such as fuel combustion, ink-jet printing, and the coating and washing of various products. The Chicago findings could have practical importance, comments David Quere of College de France in Paris, because they have revealed "a new and very efficient way to prevent the splash."
COPYRIGHT 2005 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2005, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

 Reader Opinion

Title:

Comment:



 

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:This Week; Air pressure effects on fluid drips
Author:Weiss, P.
Publication:Science News
Date:Feb 12, 2005
Words:344
Previous Article:Asian kids' IQ lift: reading system may boost Chinese scores.(This Week)(Chinese written language enhances intelligence)
Next Article:Groovy bones: mammalian ear structure evolved more than once.(This Week)
Topics:



Related Articles
Pat Steir. (exhibit at the Robert Miller Gallery, New York, New York) (Reviews)
Spray finishing problems: causes and cures. (Finishing Newsfront)
Cascades from a dripping faucet. (study shows how viscosity affects shape of water drips) (Brief Article)
Heating, simulations get the drop on drips.(Brief Article)
"FULL OF HOT AIR" TAKES ON NEW MEANING AT NIST.(National Institute of Standards and Technology)(Brief Article)
How environmental concerns shaped modern architecture.(Inside Construction)
Controlled chaos.(Middle School)(splatter painting)
HEMTT ... soak up battery spills.(Wheeled Vehicles)(Brief Article)
Zoom in, drop out.(Letter to the Editor)
Swamp soccer.(mud-splattering sport )(Brief article)

Terms of use | Copyright © 2009 Farlex, Inc. | Feedback | For webmasters | Submit articles