Optimum Design and Experimental Study of a Very Low-Specific-Speed Centrifugal Blower Blade

Low-specific-speed centrifugal blowers are widely used in industries for compressing gases to high pressures at low flows. They have relatively low manufacturing and operating cost. However, their efficiency is fairly low as a result of relatively high leakage, disc friction and passage friction pressure loss. The purpose of this paper is to show how the performances can be improved by properly reshaping its blade profile using a developed multipoint optimization approach. The core of this approach is to build an approximate model mapping the correlation between certain blade shape parameters and corresponding aerodynamic performances. The approach is implemented by the combining a blade parameterization code, a three-dimensional viscous flow solver and several improved numerical optimization algorithms. A very low-specific speed industrial centrifugal blower with parallel hub and shroud has been selected as a reference case. The superior performances of the optimized impeller blade are demonstrated by comparing the performance improvement with that of the original blade. This is then confirmed by experimental studies.Copyright © 2009 by ASME