Integrated diffuser grille for axial fan

Abstract

An integrated diffuser grille for a coil unit includes a hub, a stack diffuser wall, a plurality of radial spokes extending between the hub and the stack diffuser wall, and a plurality of partial spokes extending inwardly from the stack diffuser wall. A radial length of the partial spokes is less than a radial length of the spokes. A plurality of circumferential elements is connected to the plurality of radial spokes between the hub and the stack diffuser wall. At least one circumferential element is connected to the plurality of partial spokes and at least one circumferential element has a non-uniform configuration about a circumference of the plurality of circumferential elements. A cross-section of the plurality of radial spokes has an airfoil-shape and at least one of a spoke pitch angle, camber angle, and chord of the airfoil-shape varies over a radial length of the plurality of spokes.

What is claimed is: 
     
         1 . An integrated diffuser grille for a coil unit comprising:
 a hub;   a stack diffuser wall;   a plurality of radial spokes extending between the hub and the stack diffuser wall;   a plurality of partial spokes extending inwardly from the stack diffuser wall, wherein a radial length of the plurality of partial spokes is less than a radial length of the plurality of spokes; and   a plurality of circumferential elements arranged between the hub and the stack diffuser wall, the plurality of circumferential elements being connected to the plurality of radial spokes, at least one circumferential element of the plurality of circumferential elements being connected to the plurality of partial spokes, at least one circumferential element of the plurality of circumferential elements having a non-uniform configuration about a circumference of the plurality of circumferential elements;   wherein a cross-section of the plurality of radial spokes has an airfoil-shape and wherein at least one of a spoke pitch angle, camber angle, and chord of the airfoil-shape varies over a radial length of the plurality of spokes   
     
     
         2 . The integrated diffuser grille according to  claim 1 , wherein the plurality of radial spokes and the plurality of partial spokes are configured to straighten an air flow as it flow across the plurality of radial spokes and the plurality of partial spokes. 
     
     
         3 . The integrated diffuser grille according to  claim 1 , wherein a stacking line defined by a mid-chord of the airfoil-shape over the radial length of at least one of the plurality of radial spokes is a straight line. 
     
     
         4 . The integrated diffuser grille according to  claim 1 , wherein each of the plurality of radial spokes includes a radially inner portion adjacent to the hub, a radially outer portion adjacent to the stack diffuser wall, and a radially middle portion disposed between the radially inner portion and the radially outer portion. 
     
     
         5 . The integrated diffuser grille according to  claim 4 , wherein the radially inner portion extends from 0% to about 20% of the radial length, the radially middle portion extends from about 20% to about 70% of the radial length, and the radially outer portion extends from about 70% to 100% of the radial length. 
     
     
         6 . The integrated diffuser grille according to  claim 4 , wherein the radially inner portion of at least one of the plurality of radial spokes has at least one of a spoke pitch angle that increases from about 45-55 degrees to about 60-65 degrees relative to a circumferential direction, a camber angle that decreases from about 15-25 degrees to about 0-5 degrees, and a chord that decreases from about 80%-85% to about 70%-75% relative to the chord at a tip section. 
     
     
         7 . The integrated diffuser grille according to  claim 4 , wherein the radially outer portion of at least one of the plurality of radial spokes has at least one of a spoke pitch angle that decreases from about 70-80 degrees to about 30-50 degrees relative to a circumferential direction, a camber angle that increases from about 0-5 degrees to about 15-25 degrees, and a chord that increases from about 65%-70% to 100% relative to the chord at a tip section. 
     
     
         8 . The integrated diffuser grille according to  claim 4 , wherein the radially middle portion of at least one of the plurality of radial spokes has at least one of a spoke pitch angle that increases from about 60-65 degrees to about 70-80 degrees relative to a circumferential direction, a camber angle that is constant between about 0-5 degrees, and a chord that decreases from about 70%-75% to about 65%-70% relative to the chord at a tip section. 
     
     
         9 . The integrated diffuser grille according to  claim 1 , wherein each of the plurality of partial spokes has an airfoil-shape and a configuration of the plurality of partial spokes is substantially identical to a configuration of the plurality of radial spokes at a same radial position. 
     
     
         10 . The integrated diffuser grille of  claim 1 , wherein the hub, stack diffuser wall, plurality of radial spokes, plurality of partial spokes, and plurality of circumferential elements are integrally formed as a single unitary structure, the single unitary structure being formed from a non-metal material. 
     
     
         11 . The integrated diffuser grille according to  claim 10 , wherein the single unitary structure is formed from a plastic material. 
     
     
         12 . The integrated diffuser grille according to  claim 1 , wherein the plurality of circumferential elements have an upstream side and a downstream side, and the upstream side of the at least one circumferential element has a non-uniform contour. 
     
     
         13 . The integrated diffuser grille according to  claim 12 , wherein a depth increases in a direction toward the upstream side of the at least one circumferential element at a location adjacent to an interface with each of the plurality of radial spokes. 
     
     
         14 . The integrated diffuser grille according to  claim 1 , wherein the radial length of the plurality of partial spokes is less than or equal to about 40% of the radial length of the plurality of radial spokes. 
     
     
         15 . The integrated diffuser grille according to  claim 1 , further comprising a plurality of features integrally formed with the stack diffuser wall. 
     
     
         16 . The integrated diffuser grille according to  claim 15 , wherein the plurality of features are radially aligned with the plurality of radial spokes and the plurality of partial spokes. 
     
     
         17 . The integrated diffuser grille according to  claim 15 , wherein the plurality of features are arranged in groups, the groups being spaced about a periphery of the outer wall. 
     
     
         18 . The integrated diffuser grille according to  claim 1 , wherein the integrated diffuser grille is part of a top cover assembly of an air chiller unit of an air conditioning system. 
     
     
         19 . The integrated diffuser grille according to  claim 18 , wherein the top cover assembly further comprises a fan assembly, the integrated diffuser grille being positioned in overlapping arrangement with the fan assembly to restrict access to the fan assembly. 
     
     
         20 . The integrated diffuser grille according to  claim 18 , wherein the integrated diffuser grille is positioned downstream of the fan assembly relative to an airflow through the fan assembly.