Patent ID: 6945748
Filing Date: 2005-09-20
Classification: F04D

Abstract:
1. A centrifugal compressor comprising: a centrifugal impeller rotatable on an axis and having impeller vanes extending from an inlet end for fluid entry into the impeller; a compressor housing surrounding the impeller and defining therewith an annular fluid flow passage, the housing having an inlet protruding beyond the impeller inlet and configured for generally axial inlet flow and an outlet configured for generally radial outlet flow; an inlet member attached to the housing inlet and forming an extension configured for generally axial inlet flow into the housing; and a separate channel ring fixed within the housing inlet and forming therewith an annular recirculation channel extending from the inlet member to beyond the impeller inlet end, the channel formed with a smoothly diminishing annular cross section from a first slot at a forward end of the channel adjacent the inlet member to a second slot at a rearward end of the channel beyond the impeller inlet end.