COMPRESSOR WITH PORTED SHROUD FOR FLOW RECIRCULATION AND WITH NOISE ATTENUATOR FOR BLADE PASSING FREQUENCY NOISE ATTENUATION, AND TURBOCHARGER INCORPORATING SAME

摘要

A compressor includes a compressor housing containing a compressor wheel and defining an inlet duct that leads air into the compressor wheel, and a wheel shroud located adjacent the blade tips and extending upstream from the blades. An annular space is defined between the wheel shroud and an inner surface of the inlet duct. The wheel shroud defines a bleed port that extends into the annular space to bleed a portion of the air entering the compressor wheel into the annular space to be recirculated back into the main flow. A noise attenuator for attenuating compressor blade passing frequency noise is formed as a blind slot located opposite the bleed port and extending for a length L from the radially inner surface of the inlet duct toward the radially outer surface of the inlet duct.