Computation of Sound Generated by Flow over a Circular Cylinder: an Acoustic Analogy Approach*
نویسندگان
چکیده
The sound generated by viscous ow past a circular cylinder is predicted via the Lighthill acoustic analogy approach. The two dimensional ow eld is predicted using two unsteady Reynolds-averaged Navier-Stokes solvers. Flow eld computations are made for laminar ow at three Reynolds numbers (Re = 1000, Re = 10; 000, and Re = 90; 000) and two di erent turbulent models at Re = 90; 000. The unsteady surface pressures are utilized by an acoustics code that implements Farassat's formulation 1A to predict the acoustic eld. The acoustic code is a 3-D code|2-D results are found by using a long cylinder length. The 2-D predictions overpredict the acoustic amplitude; however, if correlation lengths in the range of 3 to 10 cylinder diameters are used, the predicted acoustic amplitude agrees well with experiment.
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