9 Vaned Diffuser Design Available to Purchase

This chapter describes a systematic procedure for the aerodynamic design of conventional vaned diffusers based on Aungier (1988a, 1990). The term conventional vaned diffusers refers to the various thin-vaned or airfoil style vaned diffusers as illustrated in Fig. 9-1. The conventional vaned diffuser relies on standard cascade technology where the swirl velocity component is reduced by turning vanes. Two other basic types of vaned diffuser are in common use today. The thick-vaned styles includes the popular vane island or channel diffuser and the pipe diffuser. These styles are patterned more after classical exhaust diffusers, where the rate of increase in passage area is controlled by increasing the vane thickness with radius. At the exit of the vanes, there is an abrupt and substantial area increase due to the large vane thickness. In recent years, the low-solidity vaned diffuser has received considerable attention. Here, very short vanes, or few in number, are used such that the vanes are too far apart to form an aerodynamic throat.