0
Gas Turbines: Combustion, Fuels, and Emissions

The Use of Perforated Damping Liners in Aero Gas Turbine Combustion Systems

[+] Author and Article Information
Jochen Rupp1

 Department of Aeronautical and Automotive Engineering, Loughborough University, United Kingdom

Jon Carrotte

 Department of Aeronautical and Automotive Engineering, Loughborough University, United Kingdom

Michael Macquisten

 Rolls-Royce plc, Derby, United Kingdom

1

On secondment from Rolls-Royce plc.

J. Eng. Gas Turbines Power 134(7), 071502 (May 23, 2012) (10 pages) doi:10.1115/1.4005972 History: Received July 24, 2011; Revised August 12, 2011; Published May 23, 2012; Online May 23, 2012

This paper considers the use of perforated porous liners for the absorption of acoustic energy within aero style gas turbine combustion systems. The overall combustion system pressure drop means that the porous liner (or “damping skin”) is typically combined with a metering skin. This enables most of the mean pressure drop, across the flame tube, to occur across the metering skin with the porous liner being exposed to a much smaller pressure drop. In this way porous liners can potentially be designed to provide significant levels of acoustic damping, but other requirements (e.g., cooling, available space envelope, etc) must also be considered as part of this design process. A passive damper assembly was incorporated within an experimental isothermal facility that simulated an aero-engine style flame tube geometry. The damper was therefore exposed to the complex flow field present within an engine environment (e.g., swirling efflux from a fuel injector, coolant film passing across the damper surface, etc.). In addition, plane acoustic waves were generated using loudspeakers so that the flow field was subjected to unsteady pressure fluctuations. This enabled the performance of the damper, in terms of its ability to absorb acoustic energy, to be evaluated. To complement the experimental investigation a simplified one-dimensional (1D) analytical model was also developed and validated against the experimental results. In this way not only was the performance of the acoustic damper evaluated, but also the fundamental processes responsible for this measured performance could be identified. Furthermore, the validated analytical model also enabled a wide range of damping geometry to be assessed for a range of operating conditions. In this way damper geometry can be optimized (e.g., for a given space envelope) while the onset of nonlinear absorption (and hence the potential to ingest hot gas) can also be identified.

Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Acoustic energy absorption by a single orifice [7]

Grahic Jump Location
Figure 2

Measured linear and nonlinear absorption characteristic of a single orifice [7]

Grahic Jump Location
Figure 3

Schematic of test facility

Grahic Jump Location
Figure 4

Mean pressure distribution along damper surface

Grahic Jump Location
Figure 5

Pressure amplitude mode shape example

Grahic Jump Location
Figure 6

Comparison of measured reflection coefficients

Grahic Jump Location
Figure 7

Reflection coefficients of various liner separations

Grahic Jump Location
Figure 8

Schematic of analytical model

Grahic Jump Location
Figure 9

Rayleigh conductivity model as in Howe [3]

Grahic Jump Location
Figure 10

Cavity pressure ratio comparison between the experiment (Exp.) and the model

Grahic Jump Location
Figure 11

Comparison between predicted and measured energy loss

Grahic Jump Location
Figure 12

Normalized mode shape pressure amplitudes at various frequencies

Grahic Jump Location
Figure 13

Comparison between experiment and modified model with pressure mode shape input function

Grahic Jump Location
Figure 14

Cavity pressure ratio variation with liner separation, experiment with fuel injector

Grahic Jump Location
Figure 15

Phase angle between cavity pressure amplitude and excitation pressure amplitude, experiment with fuel injector

Grahic Jump Location
Figure 16

Unsteady velocity amplitudes with varying liner separation

Grahic Jump Location
Figure 17

Normalized loss for varying damping skin mean pressure drop

Grahic Jump Location
Figure 18

Cavity pressure ratio with varying damping skin mean pressure drop

Grahic Jump Location
Figure 19

Estimate of pressure amplitude for hot gas ingestion

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In