Stall margin improvement of rotor fan for a vaneaxial blower system

Abstract

A vaneaxial blower system has an axis of rotation and includes a stator and a rotor fan. The stator and the rotor include blades. Each blade extends from a leading edge to a trailing edge. An angle beta of each blade is defined as a slope of a camber line at a location along a span of the blade. An angle theta of each blade is defined as an angle measured between a vertical axis extending through the axis of rotation and a radius at the location along the span of the blade. The angle beta and the angle theta for the blades are selected to provide improved performance of the vaneaxial blower system.

What is claimed is: 
     
         1 . A vaneaxial blower system having an axis of rotation, the vaneaxial blower system comprising:
 a rotor fan; and   a stator including a stator shroud, a stator inlet, a stator outlet, a stator hub, and stator blades extending from the stator hub to the stator shroud, wherein a first stator blade of the stator blades extends from a leading edge to a trailing edge, wherein an angle beta is defined as a slope of a camber line at a location along a span of the first stator blade, and wherein an angle theta is defined as an angle measured between a vertical axis extending through the axis of rotation and a radius at the location along the span of the first stator blade;   wherein at the stator hub, the angle beta for the leading edge is in the range of −3 degrees to −43 degrees and the angle beta for the trailing edge is in the range of 11 degrees to −29 degrees, the angle theta for the leading edge is 8 degrees to −32 degrees and the angle theta for the trailing edge is in the range of −7 degrees to −47 degrees; and   wherein at the stator shroud, the angle beta for the leading edge is in the range of −27 degrees to −67 degrees and the angle beta for the trailing edge is in the range of −2 degrees to −42 degrees, the angle theta for the leading edge is 8 degrees to −32 degrees and the angle theta along for trailing edge is in the range of −7 degrees to −47 degrees.   
     
     
         2 . The vaneaxial blower system of  claim 1 , wherein at a span half a distance between the stator hub and the stator shroud, the angle beta for the leading edge is in the range of −16 degrees to −56 degrees and the angle beta for the trailing edge is in the range of 6 degrees to −34 degrees, the angle theta for the leading edge is 8 degrees to −32 degrees and the angle theta for the trailing edge is in the range of −7 degrees to −47 degrees. 
     
     
         3 . The vaneaxial blower system of  claim 1  further comprising a rotor housing extending around the rotor fan, the rotor housing defining a rotor inlet and a rotor outlet, wherein system airflow enters the rotor inlet, flows into the stator inlet from the rotor outlet, and exits from the stator outlet. 
     
     
         4 . The vaneaxial blower system of  claim 3 , wherein the rotor housing and the stator shroud are coupled together. 
     
     
         5 . The vaneaxial blower system of  claim 3 , wherein the rotor fan includes a rotor shroud including a flared inlet section. 
     
     
         6 . The vaneaxial blower system of  claim 5  further comprising a lip section positioned against the flared inlet section of the rotor shroud, wherein the lip section and the flared inlet section define a recirculation inhibitor restricting airflow recirculation through a recirculation chamber between the rotor shroud and the rotor housing. 
     
     
         7 . The vaneaxial blower system of  claim 5 , wherein the rotor shroud further includes a first rim, the flared inlet section extending from the first rim. 
     
     
         8 . The vaneaxial blower system of  claim 7 , wherein the flared inlet section has a curved or angled cross-sectional shape. 
     
     
         9 . A vaneaxial blower system having an axis of rotation, the vaneaxial blower system comprising:
 a stator; and   a rotor fan including a rotor hub, a rotor shroud, a rotor inlet, a rotor outlet, and rotor blades, wherein a first rotor blade of the rotor blades extends from a leading edge to a trailing edge, wherein an angle beta is defined as a slope of a camber line at a location along a span of the first rotor blade, and wherein an angle theta is defined as an angle measured between a vertical axis extending through the axis of rotation and a radius at the location along the span of the first rotor blade;   wherein at the rotor hub, the angle beta for the leading edge is in the range of 60 degrees to 100 degrees and the angle beta for the trailing edge is in the range of 20 degrees to 60 degrees, the angle theta for the leading edge is −43 degrees to −83 degrees and the angle theta for the trailing edge is in the range of −7 degrees to −47 degrees; and   wherein at the rotor shroud, the angle beta for the leading edge is in the range of 57 degrees to 97 degrees and the angle beta for the trailing edge is in the range of 40 degrees to 80 degrees, the angle theta for the leading edge is −57 degrees to −97 degrees and the angle theta for the trailing edge is in the range of −25 degrees to −65 degrees.   
     
     
         10 . The vaneaxial blower system of  claim 9  further comprising a rotor housing extending around the rotor fan, the rotor housing defining the rotor inlet and the rotor outlet, the stator including stator inlet and a stator outlet, wherein system airflow enters the rotor inlet, flows into the stator inlet from the rotor outlet, and exits from the stator outlet. 
     
     
         11 . The vaneaxial blower system of  claim 10 , wherein the rotor shroud includes a flared inlet section. 
     
     
         12 . The vaneaxial blower system of  claim 11  further comprising a lip section positioned against the flared inlet section of the rotor shroud, wherein the lip section and the flared inlet section define a recirculation inhibitor restricting airflow recirculation through a recirculation chamber between the rotor shroud and the rotor housing. 
     
     
         13 . The vaneaxial blower system of  claim 12 , wherein the recirculation inhibitor includes a sealing member coupled to the rotor housing and extending radially towards the rotor shroud. 
     
     
         14 . The vaneaxial blower system of  claim 9 , wherein at a span half a distance between the rotor hub and a tip of the rotor blades, the angle beta for the leading edge is in the range of 50 degrees to 90 degrees and the angle beta for the trailing edge is in the range of 35 degrees to 75 degrees, the angle theta for the leading edge is −48 degrees to −88 degrees and the angle theta for the trailing edge is in the range of −14 degrees to −54 degrees. 
     
     
         15 . A vaneaxial blower system having an axis of rotation, the vaneaxial blower system comprising:
 a stator including a stator shroud, a stator inlet, a stator outlet, a stator hub, and stator blades extending from the stator hub to the stator shroud, wherein a first stator blade of the stator blades extends from a leading edge to a trailing edge, wherein an angle beta of the first stator blade is defined as a slope of a camber line at a location along a span of the first stator blade, and wherein an angle theta of the first stator blade is defined as an angle measured between a vertical axis extending through the axis of rotation and a radius at the location along the span of the first stator blade; and   a rotor fan including a rotor hub, a rotor shroud, a rotor inlet, a rotor outlet, and rotor blades, wherein a first rotor blade of the rotor blades extends from a leading edge to a trailing edge, wherein an angle beta of the first rotor blade is defined as a slope of a camber line at a location along a span of the first rotor blade, and wherein an angle theta of the first rotor blade is defined as an angle measured between a vertical axis extending through the axis of rotation and a radius at the location along the span of the first rotor blade;   wherein at the stator hub, the angle beta for the leading edge of the first stator blade is in the range of −3 degrees to −43 degrees and the angle beta for the trailing edge of the first stator blade is in the range of 11 degrees to −29 degrees, the angle theta for the leading edge of the first stator blade is 8 degrees to −32 degrees and the angle theta for the trailing edge of the first stator blade is in the range of −7 degrees to −47 degrees; and, wherein at a span at the stator shroud, the angle beta for the leading edge of the first stator blade is in the range of −27 degrees to −67 degrees and the angle beta for the trailing edge of the first stator blade is in the range of −2 degrees to −42 degrees, the angle theta for the leading edge of the first stator blade is 8 degrees to −32 degrees and the angle theta for the trailing edge of the first stator blade is in the range of −7 degrees to −47 degrees;   wherein at a span at the rotor shroud, the angle beta for the leading edge of the first rotor blade is in the range of 60 degrees to 100 degrees and the angle beta for the trailing edge is in the range of 20 degrees to 60 degrees, the angle theta for the leading edge of the first rotor blade is −43 degrees to −83 degrees and the angle theta for the trailing edge is in the range of −7 degrees to −47 degrees; and, wherein at the rotor hub, the angle beta for the leading edge of the first rotor blade is in the range of 57 degrees to 97 degrees and the angle beta for the trailing edge of the first rotor blade is in the range of 40 degrees to 80 degrees, the angle theta for the leading edge is −57 degrees to −97 degrees and the angle theta for the trailing edge of the first rotor blade is in the range of −25 degrees to −65 degrees.   
     
     
         16 . The vaneaxial blower system of  claim 15  further comprising a rotor housing extending around the rotor fan, the rotor housing defining the rotor inlet and the rotor outlet, wherein system airflow enters the rotor inlet, flows into the stator inlet from the rotor outlet, and exits from the stator outlet. 
     
     
         17 . The vaneaxial blower system of  claim 16 , wherein the rotor shroud includes a flared inlet section. 
     
     
         18 . The vaneaxial blower system of  claim 17  further comprising a lip section positioned against the flared inlet section of the rotor shroud, wherein the lip section and the flared inlet section define a recirculation inhibitor restricting airflow recirculation through a recirculation chamber between the rotor shroud and the rotor housing. 
     
     
         19 . The vaneaxial blower system of  claim 18 , wherein the recirculation inhibitor includes a sealing member coupled to the rotor housing and extending radially towards rotor shroud. 
     
     
         20 . The vaneaxial blower system of  claim 15 , wherein at a span half a distance between the stator hub to the stator shroud, the angle beta for the leading edge of the first stator blade is in the range of −16 degrees to −56 degrees and the angle beta for the trailing edge of the first stator blade is in the range of 6 degrees to −34 degrees, the angle theta for the leading edge of the first stator blade is 8 degrees to −32 degrees and the angle theta for the trailing edge of the first stator blade is in the range of −7 degrees to −47 degrees, and wherein at a span half a distance from the rotor hub to an end of the rotor blades, the angle beta for the leading edge of the first rotor blade is in the range of 50 degrees to 90 degrees and the angle beta for the trailing edge of the first rotor blade is in the range of 35 degrees to 75 degrees, the angle theta for the leading edge of the first rotor blade is −48 degrees to −88 degrees and the angle theta for the trailing edge of the first rotor blade is in the range of −14 degrees to −54 degrees.