Featured Research

from universities, journals, and other organizations

Patented 'noise sponge' quiets combustion

Date:
May 1, 2012
Source:
University of Alabama
Summary:
Breakthrough technology decreases the noise generated by combustion systems at the source by placing a sponge-like material directly in the flame.

University of Alabama engineering professor Dr. Ajay Agrawal, left, with graduate students Justin Williams, right, and Joseph Meadows, center, examine the noise reduction device, or noise sponge.
Credit: Zach Riggins, University of Alabama

A sponge-like material employed by a University of Alabama engineering professor can significantly quiet combustion, possibly making work environments safer and extending the life of equipment.

Dr. Ajay K. Agrawal, the Robert F. Barfield Endowed Chair and professor of mechanical engineering, was recently granted a patent for the breakthrough technology for noise reduction in combustion.

This technology decreases the noise generated by combustion systems at the source by placing a sponge-like material directly in the flame. This patent is based on Agrawal's work on jet engine combustion with Ultramet Corp., funded by the U.S. Navy.

The combustion process in several engines, especially those of jets, produces a deafening noise that can also be devastating to the engine. Because the noise level is so high, the sound waves produced can cause intense pulsations. These pulsations shake the engine and result in mechanical failure. The more the engine is exposed to these intense acoustic pulsations, the more likely it is to break down.

So far, noise reduction has been addressed after-the-fact, suppressing the noise outside the engine after the combustion process takes place. Agrawal's technology eliminates the noise at the source, during the combustion process.

The challenge of cutting the sound level during the combustion process is that combustion happens at extremely high temperatures and pressure. Most material cannot withstand such conditions. However, Agrawal found a porous material that can tolerate the conditions of jet engine combustion.

This porous inert material, or foam, is a composite material made of hafnium carbide and silicon carbide. It can withstand intense levels of heat and pressure. The material is placed directly into the flame and acts like a sponge for the noise.

Due to its high permeability, the foam allows gases to easily flow so combustion is not interrupted, yet is much quieter. The foam surrounds the flame, cuts the noise and eliminates the potential for engine instability.

"Experimenting with combustion can be quite noisy and unstable, shaking the whole building, but when you put the foam in place, you can talk to the person next to you. It's a night and day difference," Agrawal said.

This technology reduces noise at its source, minimizing the need for bulky and expensive modifications to exhaust equipment. It also increases the uniformity of the combustion and allows for retrofitting of existing systems, which is highly cost efficient. This technology will be useful in gas turbines, burners, furnaces, power generators and other industrial devices using combustion.

The application of the technology extends beyond jet engines. Some chemical manufacturers place loud, high-capacity torches at ground level instead of safer heights to control noise. Factories that rely on combustion also face government regulations to protect employees from noise.


Story Source:

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


Cite This Page:

University of Alabama. "Patented 'noise sponge' quiets combustion." ScienceDaily. ScienceDaily, 1 May 2012. <www.sciencedaily.com/releases/2012/05/120501182757.htm>.
University of Alabama. (2012, May 1). Patented 'noise sponge' quiets combustion. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2012/05/120501182757.htm
University of Alabama. "Patented 'noise sponge' quiets combustion." ScienceDaily. www.sciencedaily.com/releases/2012/05/120501182757.htm (accessed September 16, 2014).

Share This



More Matter & Energy News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

Newsy (Sep. 16, 2014) MIT developed a robot modeled after a cheetah. It can run up to speeds of 10 mph, though researchers estimate it will eventually reach 30 mph. Video provided by Newsy
Powered by NewsLook.com
Manufacturer Prints 3-D Car In Record Time

Manufacturer Prints 3-D Car In Record Time

Newsy (Sep. 15, 2014) Automobile manufacturer Local Motors created a drivable electric car using a 3-D printer. Printing the body only took 44 hours. Video provided by Newsy
Powered by NewsLook.com
Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Reuters - US Online Video (Sep. 15, 2014) New York officials unveil subway tunnels that were refurbished after Superstorm Sandy. Nathan Frandino reports. 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