High Helmholtz Sound Prediction Generated by Confined Flows and Propagation within Ducts

作者:Bayati Morteza*; Tadjfar Mehran
来源:International Journal of Acoustics and Vibrations, 2015, 20(1): 47-55.
DOI:10.20855/ijav.2015.20.1368

摘要

A hybrid method for the computation of noise radiation by a confined flow is used in this study. The proposed approach is appropriate and quite powerful for high Helmholtz numbers (i.e. when the turbulence/body interaction region is acoustically non-compact). The validation of this method is checked by comparing it with the analytical results of the tailored Green's function to the spinning of two vortex filaments in an infinite 2-D duct. The method is applied to the prediction of sound in a duct obstructed by a diaphragm. The sound sources generated by the fluctuations in the flow field are computed by means of an incompressible Large Eddy Simulation (LES). These sources are fed into a 2-D acoustic propagation Boundary Element Model (BEM). The predicted total acoustic power is 1.8 dB higher than the result obtained in the literature by Direct Numerical Calculation (DNC) and extrapolated experimental data for the same pipe configuration.

  • 出版日期2015-3

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