Establishment of a High Quality Database for the Acoustic Modeling of Perforated Liners

Perforated liners, especially in combination with a bias flow, are very effective sound absorbers. When appplied to gas turbine combustors, they can suppress thermo-acoustic instabilities and thus allow the application of new combustion concepts concerning higher efficiency and lower emissions. While the successful application of such a damping concept has been shown, it is still not possible to accurately predict the damping performance of a given configuration. This paper provides a comprehensive database of high quality experimental data. Variations of geometric, fluid mechanic, and acoustic parameters have been studied, including realistic engine configurations. The results demonstrate each parameter influence on the damping performance. A low order thermo-acoustic model is used to simulate the test configurations numerically. The model shows a good agreement with the measurements for a wide range of geometries and Strouhal and bias flow Mach numbers.