Dipole and Quadrupole Broadband Noise Sources

Simcenter STAR-CCM+ provides various models that allow you to compute the local acoustic power of dipole noise sources (generated per unit surface) and quadrupole noise sources (generated per unit volume). Additionally, these models allow you to qualify the suitability of a mesh ahead of a transient calculation by analyzing the frequency that the mesh can resolve.

The following model allows you to compute dipole noise sources:

Curle: The Curle model evaluates the noise from a turbulent boundary layer flow over a solid body at low Mach number. Specifically, this model evaluates the local acoustic power of dipole noise sources (generated per per unit surface), that is, noise coming from the fluctuating surface pressure from solid boundaries acting on the fluid. This model assumes isotropic turbulence.; The Curle model is typically used for air handling subsystem (AHS) applications, including rotating parts (such as blowers), heat exchangers, mufflers, distribution ducts and wall-enclosed spaces.; For more information, see Noise Source Models Reference—Curle.

The following noise source models allow you to compute quadrupole noise sources:

Proudman: The Proudman model evaluates the local acoustic power of quadrupole noise sources (noise generated per unit volume), such as around blower blades. This model assumes isotropic turbulence.; Similar to the Curle model, the Proudman model is typically used for air handling subsystem (AHS) applications, including rotating parts (such as blowers), heat exchangers and distribution ducts.; For more information, see Noise Source Models Reference—Proudman.
Goldstein (axisymmetric): The Goldstein model is based on Lighthill’s theory for predicting aerodynamic noise from a turbulent shear flow on an assumption of locally homogeneous and anisotropic turbulence.; Based on Goldstein’s theory [63], this model is a generalization of the model Ribner [81] developed for axisymmetric turbulent flow. It eliminates the Ribner assumption of the space-time correlations of Reynolds stresses.; The Goldstein model is typically used to compute the local noise contribution per unit volume for anisotropic turbulence in axisymmetric turbulent jets.; For more information, see Goldstein Model Reference.

All the above noise source models are available for steady and unsteady (transient) simulations, but are preferable for steady-state analyses. The noise source calculations are done at the end of each iteration (or time-step). The CPU time taken to run the models are similar among each other.