Abstract
Both CFD and experiment were conducted to make clear the relationship between aerodynamic broadband noise and flow fluctuations in a sirocco fan. Velocity and pressure fluctuations near the trailing edge of the rotating blades were measured experimentally, while the unsteady flow field in the sirocco fan was analyzed using CFD. In the experiment, SPL (Sound Pressure Level) was also measured at some locations outside the shroud. As a result, it was found that flow fluctuations become large near the tongue that is the bifurcation between two flow passages. These results suggest that those flow fluctuations are associated with generation of the aerodynamic broadband noise.
