Towards Simulation of Far-Field Aerodynamic Sound from a Circular Cylinder Using OpenFoam

The low-Mach number flow-induced noise by the flow past a circular cylinder at sub-critical regime was predicted. First, to assess the accuracy of the numerical methodology, the laminar flow over a circular cylinder at the Reynolds number Re = 140 and Mach number M = 0.2 was calculated by direct solution of the unsteady compressible Navier-Stokes equations. Second, the sound generated by a circular cylinder at the Reynolds number Re = 2.2 × 104 and Mach number M = 0.06 was simulated using a technique of large-eddy simulation. For both cases, the calculated acoustic fields showed a dipole directivity, similar to a natural vortex shedding. The impact of the Doppler effect was investigated and discussed as well. In general, the computed aerodynamic and far-field acoustic results were found to be in good agreement with available experimental measurements and analytical relationships.