Effects of Reynolds Stress on Flow Noise from Vortex/hydrofoil Interactions
نویسندگان
چکیده
Acoustic field generated by a single vortex approaching a hydrofoil is studied. A combined vortex/RANS simulation for the near–field unsteady vorticity is developed to include effects from RANS Reynolds stresses. The far-field acoustics is calculated using a vortex sound formula with the near-field vorticity as the source. The results show that at a higher incident angle when the RANS shows a substantial region with strong Reynolds stresses, there is a significant increase in the sound level due to enhanced unsteady vorticity in the shed vortices near the trailing edge.
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