High Fidelity Modeling of Acoustic Liners For Aeronautical Applications

TitleHigh Fidelity Modeling of Acoustic Liners For Aeronautical Applications
Publication TypeConference Paper
Year of PublicationIn Press
AuthorsPinelli L, Marconcini M, Arnone A, Bacci D
Conference Name34th Congress of the International Council of the Aeronautical Sciences
Conference LocationFirenze, Italy, 9-13 September 2024
Keywordsacoustic liner, aircraft noise, computational aeroacoustics (CAA)
Aircraft noise is a polluting emission from civil aviation and is the most significant cause of adverse community reactions related to the operation and expansion of airports. Reducing the population affected by significant aircraft noise is therefore a key priority for aircraft-engine designers. Acoustic liners are a well-established technology to decrease noise emissions and they have been installed in the engine intake and turbine nozzle for a long time. Such passive devices are usually designed to absorb a target band of the noise spectrum radiated from the aft and rear parts of the engine. Liner panels based on single-degree-of-freedom cavities are usually designed using semi-analytical methods and verified with experimental campaigns in dedicated grazing tube rigs. Thanks to the growth in computational capability, high-fidelity simulations of such devices are becoming viable and can be used instead of expensive experimental campaigns. This is particularly true when screening non-conventional geometries of the resonator cavity as Triply Periodic Minimal Surface (TPMS). In this context, the paper presents and validates a high-fidelity numerical approach based on the OpenFOAM open-source CFD code to predict the acoustic impedance and absorption of liner panels. LES simulations of a single resonator cell have been performed with and without grazing flow for different Sound Pressure Level (SPL) of the planar acoustic waves to investigate linear and non-linear regimes of the resonator. Liner impedance and absorption coefficients have been derived by mean of the well-known in-situ method.
Refereed DesignationRefereed