アプリケーションギャラリ

The acoustic field in a model of an axially symmetric lined aero-engine duct, based on modal sound transmission, is analyzed. The source is generated by a single mode excitation at a boundary. Sources and nonreflecting conditions are applied using port boundary conditions. The model analysis is performed in three steps, first computing the background mean flow (compressible irrotational potential flow), then analyzing the propagating modes with a boundary mode analysis, and finally solving the acoustic field in the lined flow-duct with the linearized potential flow equations. This model represents an extension of the Flow Duct model where the modes used at the ports are computed including the wall lining (impedance condition). Results are presented for the case with a background flow and for the lined duct walls.