Improvements in or relating to compressors

摘要

951,713. Axial-flow compressors. GENERAL DYNAMICS CORPORATION. July 3, 1962 [July 5, 1961], No. 25533/62. Heading F1C. A blade structure suitable for use as one stage in an axial-flow compressor comprises at least a row of impulse rotor blades, and a stator blade section including a row of reaction blades and a row of impulse blades. Impulse rotor blades 11b1 are followed by reaction stator blades 12a1 and impulse reaction blades 12b1. The blades 11b1 may be preceeded by reaction rotor blades 11a1. The reaction blades 11a1 and 12a1 effect a static pressure rise by diffusion but deflect the gas through a small angle only. The impulse blades 11b1 and 12b1 turn the gas through a large angle to reverse the circumferential component of gas velocity; since this is done without appreciable pressure increase, expansion and other losses are small. The stator blades are mirror images of the respective rotor blades, and the pressure rise in the stator is substantially equal to that in the rotor, i.e., the reaction blading is of 50 % reaction type. Alternate impulse blades (those not in alignment with the preceding reaction blades) may be omitted. There may be a small pressure drop in the impulse blading, with a corresponding small increase in gas velocity. An additional row of reaction rotor blades may be provided in the final stage of the compressor to reduce the exit whirl. Specification 931,930 is referred to.