Featured Research

from universities, journals, and other organizations

Fire On The Move

Date:
September 11, 1998
Source:
Weizmann Institute
Summary:
Fire is a formidable foe, its destructive power usually advancing rapidly in chaotic patterns. Now, Weizmann Institute of Science researchers have brought fire under control in the laboratory, revealing that under certain conditions, a weak but persistent flame can advance undetected, wreaking havoc on Earth... and in space.

Fire is a formidable foe, its destructive power usually advancing rapidly in chaotic patterns. Now, Weizmann Institute of Science researchers have brought fire under control in the laboratory, revealing that under certain conditions, a weak but persistent flame can advance undetected, wreaking havoc on Earth... and in space.

Flame is notoriously difficult to study because it is rendered chaotic by convection, a phenomenon in which hot gas rises. To eliminate convection-induced complexity, Dr. Ory Zik and Prof. Elisha Moses of the Institute's Physics of Complex Systems Department "squeezed" fire into two dimensions. In their experiment, soon to be reported in PHYSICAL REVIEW LETTERS, fire propagates in a controllable manner through a sheet of paper contained in a transparent case, leaving behind a pattern of long, finger-like projections. The scientists controlled the propagation rate and the density of the fingers by adjusting the oxygen supply.

Much to their surprise, they discovered that flame dynamics are governed by the same laws that describe more stable phenomena -- for example, penetration of a liquid into a porous material. Since these laws are relatively simple, it is a real boon for scientists to know that they can also be applied to systems as unstable as fire. The theory to explain the phenomenon was developed with the help of Dr. Zeev Olami of the Chemical Physics Department.

Interestingly, at about the same time as this study, NASA's scientists launched an experiment aboard the space shuttle to examine the way fire spreads in outer space. They were amazed to discover that their flames advanced slowly but steadily like a fiery monster with finger-like projections. The NASA researchers approached the Weizmann scientists, who provided a simple explanation to this puzzling phenomenon: The astronauts had observed exactly the same finger-like pattern as in the Institute experiment, only in three dimensions. In both cases, the key element was the absence of convection. While on Earth convection was neutralized by creating a 2-D system, in space, convection was absent because in zero-gravity hot air doesn't rise.

Thus, the Weizmann experiment provides a low-cost terrestrial alternative to studying the spread of fire aboard spacecraft. Moreover, it makes it possible to establish criteria for detecting slow-moving low-convection flame. Such fires are particularly dangerous because they may not generate enough smoke and heat to activate regular smoke detectors.

Apart from fire detection in outer space, a better understanding of flame dynamics may help detect flames that propagate through panel-enclosed surfaces. This would be crucial for airplane safety, where even a small fire can lead to catastrophe.

Dr. Olami holds the Morris and Ida Wolf Career Development Chair.

###

The Weizmann Institute of Science, in Rehovot, Israel, is one of the world's foremost centers of scientific research and graduate study. Its 2,500 scientists, students, technicians, and engineers pursue basic research in the quest for knowledge and the enhancement of the human condition. New ways of fighting disease and hunger, protecting the environment, and harnessing alternative sources of energy are high priorities.


Story Source:

The above story is based on materials provided by Weizmann Institute. Note: Materials may be edited for content and length.


Cite This Page:

Weizmann Institute. "Fire On The Move." ScienceDaily. ScienceDaily, 11 September 1998. <www.sciencedaily.com/releases/1998/09/980911074053.htm>.
Weizmann Institute. (1998, September 11). Fire On The Move. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/1998/09/980911074053.htm
Weizmann Institute. "Fire On The Move." ScienceDaily. www.sciencedaily.com/releases/1998/09/980911074053.htm (accessed September 1, 2014).

Share This




More Matter & Energy News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Australian Airlines Relax Phone Ban Too

Australian Airlines Relax Phone Ban Too

Reuters - Business Video Online (Aug. 26, 2014) Qantas and Virgin say passengers can use their smartphones and tablets throughout flights after a regulator relaxed a ban on electronic devices during take-off and landing. As Hayley Platt reports the move comes as the two domestic rivals are expected to post annual net losses later this week. Video provided by Reuters
Powered by NewsLook.com
Hurricane Marie Brings Big Waves to California Coast

Hurricane Marie Brings Big Waves to California Coast

Reuters - US Online Video (Aug. 26, 2014) Huge waves generated by Hurricane Marie hit the Southern California coast. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Chinese Researchers Might Be Creating Supersonic Submarine

Chinese Researchers Might Be Creating Supersonic Submarine

Newsy (Aug. 26, 2014) Chinese researchers have expanded on Cold War-era tech and are closer to building a submarine that could reach the speed of sound. Video provided by Newsy
Powered by NewsLook.com
Breakingviews: India Coal Strained by Supreme Court Ruling

Breakingviews: India Coal Strained by Supreme Court Ruling

Reuters - Business Video Online (Aug. 26, 2014) An acute coal shortage is likely to be aggravated as India's supreme court declared government coal allocations illegal, says Breakingviews' Peter Thal Larsen. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins