Stabilization of acoustic modes using Helmholtz and Quarter-Wave resonators tuned at exceptional points

Open access
Date
2019-04-14Type
- Journal Article
Citations
Cited 13 times in
Web of Science
Cited 16 times in
Scopus
ETH Bibliography
yes
Altmetrics
Abstract
Acoustic dampers are efficient and cost-effective means for suppressing thermoacoustic instabilities in combustion chambers. However, their design and the choice of their purging air mass flow is a challenging task, when one aims at ensuring thermoacoustic stability after their implementation. In the present experimental and theoretical study, Helmholtz (HH) and Quarter-Wave (QW) dampers are considered. A model for their acoustic impedance is derived and experimentally validated. In a second part, a thermoacoustic instability is mimicked by an electro-acoustic feedback loop in a rectangular cavity, to which the dampers are added. The length of the dampers can be adjusted, so that the system can be studied for tuned and detuned conditions. The stability of the coupled system is investigated experimentally and then analytically, which shows that for tuned dampers, the best stabilization is achieved at the exceptional point. The stabilization capabilities of HH and QW dampers are compared for given damper volume and purge mass flow. Show more
Permanent link
https://doi.org/10.3929/ethz-b-000313705Publication status
publishedExternal links
Journal / series
Journal of Sound and VibrationVolume
Pages / Article No.
Publisher
ElsevierSubject
Thermoacoustic instabilities; Helmholtz resonator; Quarter-Wave resonator; Acoustic damper; Exceptional pointOrganisational unit
09471 - Noiray, Nicolas / Noiray, Nicolas
More
Show all metadata
Citations
Cited 13 times in
Web of Science
Cited 16 times in
Scopus
ETH Bibliography
yes
Altmetrics