DESIGN OF LOW-NOISE CENTRIFUGAL BLOWERS .2. OPTIMIZATION STUDY

摘要

The influence of several impeller and housing design elements on the broadband, random noise produced by centrifugal blowers having forward-curved impellers was identified by measuring the sound power produced by each member of a family of blowers that spanned a prescribed range of one (or occasionally two) design parameter(s). The parameters that resulted in the minimum A-weighted sound power level then represented the optimal blower design, The design parameters considered were: impeller type, axial and radial inlet clearances, scroll development angle and length, and cutoff clearance, Tonal components, resulting from either impeller blade/cutoff interaction or the drive motor, were removed from the sound pressure spectra before sound power levels were calculated; thus the results apply only to the random component of the aerodynamic noise generated by centrifugal blowers. Since a blower's design influences its aerodynamic performance as well as the sound it generates, a scaling procedure was applied to account for sound power differences resulting solely from aerodynamic performance differences. (C) 1995 Institute of Noise Control Engineering.