Abstract
To improve the efficiency and to reduce the noise of a centrifugal blower, we have studied the influence of the number of blades in a vaned diffuser on aerodynamics and noise level. We have found that both the noise level and the dominating order of BPF changes with the number of blades. The change in noise level due to blade number is closely related to the characteristics of resonance. At non-resonant points, it is found from our experiments that noise change due to the number of revolution becomes smaller with the increase of blade number.
