Time-accurate Navier-Stokes computations of classical two-dimensional edge tone flow fields

Time-accurate Navier-Stokes computations were performed to study a Class II (acoustic) whistle, the edge tone, and gain knowledge of the vortex-acoustic coupling mechanisms driving production of these tones. Results were obtained by solving the full Navier-Stokes equations for laminar compressible air flow of a two-dimensional jet issuing from a slit interacting with a wedge. Cases considered were determined by varying the distance from the slit to the edge. Flow speed was kept constant at 1750 cm/sec as was the slit thickness of 0.1 cm, corresponding to conditions in the experiments of Brown. Excellent agreement was obtained in all four edge tone stage cases between the present computational results and the experimentally obtained results of Brown. Specific edge tone generated phenomena and further confirmation of certain theories concerning these phenomena were brought to light in this analytical simulation of edge tones.