Centrifugal compressor for a turbocharger, having synergistic ported shroud and inlet-adjustment mechanism

摘要

A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between a closed position, an open position, and a super-open position. The compressor also includes a ported shroud system. The inlet-adjustment mechanism includes a plurality of blades disposed about the air inlet and movable radially inwardly and outwardly for defining the various positions. In the closed position, the effective diameter of air inlet is reduced and the blades block flow through the ported shroud system. In the open position, the blades still block the ported shroud but the effective inlet diameter is increased relative to the closed position. In the super-open position, the blades unblock the ported shroud so that an additional amount of flow can pass through the ported shroud, thereby shifting the compressor's choke flow line to higher flow rates.