Controlled Area Progression Vaned Diffuser

Abstract

A controlled area progression vaned diffuser (CAPVD) for a compressor may be defined by a bearing diffuser wall of a bearing housing and a compressor diffuser wall of a compressor housing that are spaced apart in the axial direction, with a plurality of vanes extending between the diffuser walls and circumferentially spaced about a rotational axis of a compressor wheel. Airflow from the compressor wheel enters the CAPVD through a diffuser inlet, flows between the diffuser walls and past the vanes, and flows out of a diffuser outlet to a volute. The diffuser walls may be shaped so that a width of pinch point between the diffuser inlet and the vanes is less than a width at the vanes, and a width of the diffuser outlet is less than the width at the vanes.

What is claimed is: 
     
         1 . A controlled area progression vaned diffuser (CAPVD) for a compressor, wherein the compressor includes a bearing housing in which a shaft is supported by a bearing to rotate about a rotational axis, a compressor wheel disposed on the shaft and having a compressor radius, and a compressor housing connected to the bearing housing, defining a chamber within which the compressor wheel rotates and a volute for receiving airflow generated by the compressor wheel, the CAPVD comprising:
 a bearing diffuser wall of the bearing housing having an annular shape and extending from the chamber to the volute;   a compressor diffuser wall of the compressor housing having an annular shape and extending from the chamber to the volute, wherein the bearing diffuser wall and the compressor diffuser wall are spaced apart in an axial direction;   a plurality of vanes extending from the bearing diffuser wall and the compressor diffuser wall and circumferentially spaced about the rotational axis, each vane have a vane leading edge and a vane trailing edge;   a diffuser inlet proximate the chamber; and   a diffuser outlet proximate the volute, wherein the airflow from the compressor wheel enters the CAPVD through the diffuser inlet, between the bearing diffuser wall and the compressor diffuser wall and past the plurality of vanes, and flows out of the diffuser outlet to the volute,   wherein the bearing diffuser wall and the compressor diffuser wall are spaced apart by a vane leading edge width at the vane leading edge,   wherein the bearing diffuser wall and the compressor diffuser wall define a pinch point between the diffuser inlet and the vane leading edge, wherein pinch point has a pinch point width that is less than the vane leading edge width, and   wherein the diffuser outlet has a diffuser outlet width that is less than the vane leading edge width.   
     
     
         2 . The CAPVD of  claim 1 , wherein a diffuser inlet width at the diffuser inlet is greater than the pinch point width. 
     
     
         3 . The CAPVD of  claim 2 , wherein the diffuser inlet width is with a range from 0.04 to 0.07 times the compressor radius. 
     
     
         4 . The CAPVD of  claim 2 , wherein the diffuser inlet width is less than the vane leading edge width. 
     
     
         5 . The CAPVD of  claim 2 , wherein the vane leading edge width is within a range from 0.7 to 1.2 times the diffuser inlet width. 
     
     
         6 . The CAPVD of  claim 2 , wherein the diffuser outlet width is within a range from 0.7 to 1.2 times the diffuser inlet width. 
     
     
         7 . The CAPVD of  claim 2 , wherein the pinch point width is within a range from 0.6 to 1.0 times the diffuser inlet width. 
     
     
         8 . The CAPVD of  claim 1 , wherein a diffuser outlet radius from the rotational axis to the diffuser outlet is within a range from 1.45 to 2.0 times the compressor radius. 
     
     
         9 . The CAPVD of  claim 1 , wherein a pinch point radius from the rotational axis to the pinch point is within a range from 1.05 to 1.3 times the compressor radius. 
     
     
         10 . The CAPVD of  claim 1 , wherein a vane leading edge radius from the rotational axis to the vane leading edge is within a range from 1.1 to 1.4 times the compressor radius. 
     
     
         11 . The CAPVD of  claim 1 , wherein the vane leading edge radius is within a range from 1.3 to 1.4 times the compressor radius. 
     
     
         12 . The CAPVD of  claim 1 , wherein a vane trailing edge radius from the rotational axis to the vane trailing edge is within a range from 1.3 to 1.7 times the compressor radius. 
     
     
         13 . The CAPVD of  claim 1 , wherein the bearing diffuser wall and the compressor diffuser wall are spaced apart by a vane trailing edge width at the vane trailing edge, and wherein the vane trailing edge width is equal to the vane leading edge width. 
     
     
         14 . The CAPVD of  claim 1 , wherein an axial distance between the bearing diffuser wall and the compressor diffuser wall decreases at a constant rate from the diffuser inlet to the pinch point. 
     
     
         15 . The CAPVD of  claim 1 , wherein an axial distance between the bearing diffuser wall and the compressor diffuser wall increases at a constant rate from the pinch point to the vane leading edge. 
     
     
         16 . The CAPVD of  claim 1 , wherein an axial distance between the bearing diffuser wall and the compressor diffuser wall decreases at a constant rate from the vane trailing edge to the diffuser outlet.