| 摘要 |
A two-stage diffuser is disclosed which is intended to be used with a high pressure ratio centrifugal compressor. The first stage comprises a vaneless diffuser passage having rotating sidewalls that freely turn on bearings mounted coaxially with the compressor rotor. The second stage comprises a stationary vaned-type diffuser. In combination, the two stages provide a compact diffuser having improved efficiency. Gas flow leaving the compressor from the periphery of the impeller at supersonic speed contacts the moving sidewalls of the rotary diffuser stage. By having these walls travel at nearly half the speed of the impeller, relative difference in speed between the gas and the walls is subsonic, hence, no shock wave occurs. Expansion of the gas in the first rotary diffuser stage makes it possible to deliver subsonic gas to the vaned second stage.
|
