Compressor stage of a turbocharger with flow amplifier

摘要

An energy recovery system and method is provided for the compressor stage of a turbocharger during surge avoidance operation. The compressor stage includes a housing defining an inlet, an inlet chamber, a diffuser and a volute. A flow amplifier is provided in the compressor housing or in a separate element. If the compressor stage is operating near a surge condition, charge air from a system charge air source is routed to the flow amplifier which discharges the air substantially along the inner peripheral surface of the inlet chamber in a downstream direction relative to the air intake flow direction. The charge air is supplied in a substantially annular manner at an increased velocity such that at least a portion of the intake air flow is entrained by the charge air so as to increase the velocity of the air toward the compressor wheel and recovering energy of the charge air.

主权项

1. A compressor stage (50) for a turbocharger (100) comprising:
a compressor housing (52) housing a compressor wheel (18) and defining at least in part an inlet (54) for receiving an inlet air flow (77), an inlet chamber (56) through which the inlet air flows from the inlet (54) towards the compressor wheel, a diffuser (58) and a volute (60); a flow amplifier (64) having an inlet (68) and an outlet (70), the outlet (70) separating the inlet chamber into an upstream portion upstream of the outlet (70) and a downstream portion downstream of the outlet (70), control means to permit introduction of compressed fluid to the inlet (68) of the flow amplifier (64) upon detection of a surge condition during operation of the turbocharger (100) and to block introduction of compressed fluid into the inlet (68) of the flow amplifier in the absence of detection of a surge condition, wherein the outlet (70) of the flow amplifier (64) is configured to discharge a jet of compressed fluid such that the discharged compressed fluid flows substantially along an inner peripheral surface (57) of the downstream portion of the inlet chamber in accordance with the Coanda effect and to entrain fluid flowing from the upstream portion of the inlet chamber into the downstream portion of the inlet chamber, increasing the velocity of at least a portion of the inlet air flow (77) in the downstream portion of the inlet chamber, the outlet (70) being oriented in a downstream direction of fluid flow in the inlet chamber (56).