アプリケーションギャラリ

This model demonstrates two approaches to model the acoustics in a generic nacelle with an acoustic liner and a background flow. The first method uses the Compressible Potential Flow and the* Linearized Potential Flow, Frequency Domain* interfaces, while the second, more detailed approach, uses a turbulent background flow and the Linearized Navier–Stokes, Frequency Domain interface.

In the first approach, based on a linearized potential flow equations, the acoustic liner is modeled using the Brambley option for the impedance condition. This is an extended version of the Ingard–Myers boundary condition which takes into account the thickness of the turbulent boundary layer of the background flow field. A propagating acoustic mode with a radial and azimuthal wave number is actuated using a Port condition.

In the second approach, based on the linearized Navier–Stokes equations, the propagating modes are found with the Linearized Navier–Stokes, Boundary Mode interface and then used as a background field to excite the system with the correct acoustic mode. The results of the two approaches are compared.