New material could make aircraft as quiet as a hair dryer - increasing passenger comfort and reducing noise by up to 80%
An incredibly light new material can reduce aircraft engine noise and increase passenger comfort. Airgel made of graphene oxide and polyvinyl alcohol weighs only 2.1 kg per cubic meter, which makes it the lightest sound insulation ever made. This material was developed at the University of Bath.
Airgel made of graphene oxide and polyvinyl alcohol weighs only 2.1 kg per cubic meter , which makes it the lightest sound insulation ever made. It could be used as insulation in aircraft engines to reduce noise by up to 16 decibels – reducing the 105-decibel noise of a jet engine to a sound similar to that of a hair dryer.
The airgel's "meringue"-like structure makes it extremely light, meaning it could act as an insulator in aircraft engine nacelles without increasing overall weight. The material is currently being further optimized by the research team to offer better heat dissipation, which is beneficial in terms of fuel efficiency and safety .
Researchers from Bath's Materials and Structures Center (MAST) have published a method for producing the materials in the journal Nature Scientific Reports.
Professor Michele Meo, who led the research, says: "It's clearly a very exciting material that could be used in many ways - initially in aerospace, but potentially in many other areas such as automotive and maritime as well as construction. We managed to produce such an extremely low density using a liquid combination of graphene oxide and polymer, which are formed by whipped air bubbles and cast by freezing. At a very basic level, the technique can be likened to whipping egg whites, hence the name 'meringue' - it's firm but contains lots of air, so there's no reduction in weight or efficiency to achieve a big improvement in comfort and noise."
Although the team initially focused on working with partners in the aerospace industry to test the material as a sound insulator in aircraft engines, they say it could also be used to create panels in helicopters or car engines. They estimate that the airgel could be used within 18 months.
University of Bath. “The material could make an airplane as quiet as a hairdryer: Extremely low-density graphene-based airgel can improve passenger comfort and reduce noise by up to 80%. ScienceDaily. ScienceDaily, 18 June 2021.www.sciencedaily.com/releases/2021/06/210618091625.htm.