Time-domain characterization of the acoustic damping of a perforated liner with bias flow
Date of Issue2012
School of Mechanical and Aerospace Engineering
Combustioninstabilities are caused by the interaction of unsteady heat releases and acoustic waves. To mitigate combustioninstabilities, perforated liners, typically subjected to a low Mach number bias flow (a cooling flow through perforated holes), are fitted along the bounding walls of a combustor. They dissipate the acoustic waves by generating vorticity at the rims of perforated apertures. To investigate the absorption of plane waves by a perforated liner with bias flow, a time-domain numerical model of a cylindrical lined duct is developed. The liners’ damping mechanism is characterized by using a time-domain “compliance.” The development of such time-domain compliance is based on simplified or unsimplified Rayleigh conductivity. Numerical simulations of two different configurations of lined duct systems are performed by combining a 1D acoustic wavemodel with the compliance model. Comparison is then made between the results from the present models, and those from the experiment and the frequency-domain model of previous investigation [Eldredge and Dowling, J. Fluid Mech. 485, 307–335(2003)]. Good agreement is observed. This confirms that the present model can be used to simulate the propagation and dissipation of acoustic plane waves in a lined duct in real-time.
Mechanical and Aerospace Engineering
The journal of the acoustical society of America
© 2012 Acoustical Society of America. This paper was published in Journal of the Acoustical Society of America and is made available as an electronic reprint (preprint) with permission of Acoustical Society of America. The paper can be found at the following official DOI: [http://dx.doi.org/10.1121/1.4728197]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.