New Apparatus and Blower Centrifugal Fan Design Features to Improve its Performance

Different design philosophies of a blower centrifugal fan blades and hub are evaluated by airflow performance, computational fluid dynamic analysis (CFD) and experimental Laser Doppler Velocimetry (LDV). A design criterion of fan blade, vanes, channels is developed to eliminate or minimize air separation from the blades suction side. The effect of the fan hub design on the air radial velocity profile is discussed. A new apparatus is developed to control the air flow field at the blower inlet ring. It directs the air to flow in radial directions at the entrance of the fan blade passages, channels. The blower systems with the new features operates at high mechanical efficiency over a broad range of airflow rate in different blower scroll sizes. Its peak static efficiency reaches 62% and total mechanical efficiency 68%, which is 5 to 10% above efficiencies of previous designs. As a result, power consumption is reduced by 7–15% through the operating range.