AERODYNAMIC AND MECHANICAL DESIGN OF AN 8: PRESSURE RATIO CENTRIFUGAL COMPRESSOR

摘要

An 8:1 pressure ratio, 0.907 kg/s (2.0 lbm/s) centrifugal compressor stage has been designed and fabricated. The design proceeded subject to the specifications that (i) the stage be representative of "state-of-the-art" performance (efficiency and flow range) and (ii) the stage will be used as a "workhorse" compressor for experiments to be conducted using laser Doppler velocimeter (LDV) equipment. The final design is a 75,000 RPM, 19 blade (no splitters) impeller with an axial inducer and 30° of backward leaning at the impeller tip. An optimally matched, 17 channel, vane island diffuser was designed and built. The calculated total-to-static efficiency is 77% with a flow range of 12%, choke-to-surge, at design speed.nAll of the compressor hardware has been fabricated and inspected and the stage has been checked out for mechanical integrity at design speed under a companion program.