CENTRIFUGAL COMPRESSOR

摘要

An object is to position guide vanes for generating swirl flow at a housing inner circumferential side in front of an impeller wheel to improve a surge margin and to restrict decrease in a choke flow rate, while making the inclination angle of the guide vanes variable. A centrifugal compressor 19 includes a compressor housing 15, an impeller wheel 7 which compresses intake gas from an intake-air inlet 23, a plurality of guide vanes 63 disposed circumferentially along an inner circumferential wall of the intake-air channel 21 between the intake-air inlet 23 and the impeller wheel 7 to swirl the intake gas around the rotational axis, a central intake-air flow path 71 formed at an inner side of the guide vanes 63 to allow the intake gas to flow to the impeller wheel without passing through the guide vanes 63, and a guide-vane moving mechanism 73 which simultaneously changes the inclination angle of the guide vanes 63.