Two stage high speed centrifugal blower flow characteristics via CFD simulation.

Abstract

As the demand significantly increases in diversified applications, the development of high performance higher speed centrifugal blowers has reached urgency. Therefore, to understand the flow behaviour inside the blower becomes very important in the design stage. In order to reach a higher pressure ratio, the two stage centrifugal blower is desired. This paper adopts transient computational fluid dynamics (CFD) software with the sub-grid geometry resolution (SGGR) technique to predict the pressure-air flowrate (P-Q) curve of a two stage high speed centrifugal blower. The axial work as well as the corresponding efficiency based on the CFD results are also calculated and obtained. As the flow inside a high speed blower would be highly unstable, the design should avoid the circulation occurring inside the blower. In addition, the matching between the first and second stage also plays an important role. The CFD simulation could provide clear observation of the flow behavior which could help to improve the design and increase the blower performance.