Setting Up a Dipole and Quadrupole Noise Sources Simulation

A dipole- and quadrupole noise sources simulation allows you to compute the local acoustic power of broadband noise sources for applications such as air handling subsystems (AHS) or turbulent jets.

To set up a dipole or quadrupole noise sources simulation:
  1. Create a physics continuum and assign it to the flow region.
  2. In the physics continuum, select the following models in order:
    Group Box Model
    Space One of:
    • Two Dimensional
    • Three Dimensional
    • Axisymmetric—select this option for the analysis of quadrupole-generated broadband noise sources in axisymmetric jets.

    For more information, see Modeling Space.
    Time One of:
    • Steady (preferable)
    • Implicit Unsteady
    Material Any but solid
    Flow any
    Viscous Regime Turbulent
    Turbulence Reynolds-Averaged Navier-Stokes
    Reynolds-Averaged Turbulence any

    For more information, see Reynolds-Averaged Navier-Stokes (RANS) Turbulence Models.
    Optional Models Aeroacoustics
    Aeroacoustics Models Broadband Noise Sources
    Broadband Noise Source Models One of:
    • Goldstein (for the analysis of quadrupole-generated broadband noise sources in axisymmetric jets)
    • Noise Source Models (for the analysis of dipole- or quadrupole generated broadband noise sources in air handling subsystem (AHS) applications)
    Noise Source Models One or both of:
    • Curle (for the analysis of dipole-generated broadband noise sources)
    • Proudman (for the analysis of quadrupole-generated broadband noise sources)
  3. Select the [physics continuum] > Models > Curle, Proudman, or Goldstein node, respectively, and set the following properties:
    • Far-Field Density—the fluid density in the far field.
    • Far-Field Sound Speed—the speed of sound in the far field.
    • Reference Acoustic Power— a reference acoustic power, used for the calculation of the acoustic power per unit volume in dB.
  4. Run the simulation.
  5. After the simulation completes, analyze the following field functions using the post-processing capabilities that are available in Simcenter STAR-CCM+:
    • [noise source model] Acoustic Power
    • [noise source model] Acoustic Power DB
    where [noise source model] can be Proudman, Goldstein, or Curle Surface.
    Use plane sections to access the field function values for the Proudman and the Goldstein models. For the Curle model, you analyze the field functions on boundaries.
  6. To analyze the sound frequency that the mesh can resolve, see Qualifying the Mesh for the Desired Sound Frequency.