Patent ID: 9732756
Date: 2017-08-15
CPC Classifications: F01D,F02B,F04D,F05D,Y02T

Claim:
1. A centrifugal compressor, comprising: a housing having an intake-air inlet which opens in a direction of a rotational axis of the centrifugal compressor, and an intake-air channel which connects to the intake-air inlet; an impeller wheel disposed inside the housing rotatably around the rotational axis, and configured to compress intake gas which flows in from the intake-air inlet; a plurality of guide vanes disposed in a circumferential direction along an inner circumferential wall of the housing between the intake-air inlet and the impeller wheel and configured to swirl the intake gas flowing in from the intake-air inlet around the rotational axis; a central intake-air flow path formed at an inner circumferential side of the plurality of guide vanes and configured to allow the intake gas flowing in from the intake-air inlet to flow to the impeller wheel without passing through the guide vanes; and a guide-vane moving mechanism which simultaneously changes inclination angles of the plurality of guide vanes with respect to the direction of the rotational axis; wherein the housing includes a recirculation flow path which is disposed on an outer side of the intake-air channel and which brings an outer circumferential section of vanes of the impeller wheel into communication with the intake-air channel at an upstream side of the impeller wheel, where the housing is divided in half into an upstream housing and a downstream housing at a position where the recirculation flow path is divided, the housing being further divided into a third part comprising a shroud-side housing having an air channel of a spiral shape at a further downstream side of the downstream housing, and wherein a plurality of circulation voids are formed in the upstream housing and the downstream housing on the circumference around the rotational axis line to extend in the direction of the rotational axis line, said voids constituting the recirculation flow path.