Ducted fan with inlet vanes and deswirl vanes

Abstract

A fan apparatus includes a ducted housing with an axis of rotation including a first section and a second section. The fan apparatus further includes a first plurality of vanes being radially coupled within the first section and a second plurality of vanes being radially coupled within the second section. Additionally, the fan apparatus includes an impeller with a plurality of blades rotatably disposed within the ducted housing between the first plurality of vanes and the second plurality of vanes for rotary motion about the axis of rotation. The first plurality of vanes are stationary in a first arrangement to guide an inflow of air towards the impeller. The plurality of blades are rotary in a second arrangement to have a rotational direction substantially opposite to the inflow of air guided by the first arrangement. The second plurality of vanes are stationary in a third arrangement to diffuse an outflow of air substantially along the axis of rotation.

1 . A fan apparatus comprising:
 a ducted housing having an first section and a second section;   an impeller having a plurality of blades rotatably disposed within the second section for rotary motion about an axis of rotation, the plurality of blades being arranged in a first arrangement radially about the axis of rotation;   a first plurality of vanes fixedly disposed within the first section upstream of the impeller and arranged in a second arrangement radially about the axis of rotation; and   a second plurality of vanes fixedly disposed within the second section downstream of the impeller and arranged in a third arrangement radially about the axis of rotation;   wherein:
 the second arrangement of the first plurality of vanes is stationary with respect to the ducted housing to redirect an axial inflow of air to a direction against direction of rotation of the impeller; 
 the third arrangement of the second plurality of vanes is stationary with respect to the ducted housing to diffuse an outflow of air in a direction substantially along the axis of rotation. 
   
     
     
         2 . The fan apparatus of  claim 1  wherein each of the first plurality of vanes comprises an airfoil shape having a first leading edge facing the inflow of air and a corresponding first trailing edge. 
     
     
         3 . The fan apparatus of  claim 2  wherein:
 the first leading edge is associated with a first inlet angle measured about 10 degrees or less from a corresponding tangential direction to the axis of rotation;   the first trailing edge is associated with a first exit angle measured about 30 degrees to 60 degrees from a corresponding tangential direction to the axis of rotation.   
     
     
         4 . The fan apparatus of  claim 1  wherein each of the plurality of blades comprises an airfoil shape having a second leading edge disposed near the first trailing edge and a corresponding second trailing edge. 
     
     
         5 . The fan apparatus of  claim 4  wherein:
 the second leading edge is associated a second inlet angle measured about 40 degrees to 80 degrees from a corresponding tangential direction to the axis of rotation;   the second trailing edge is associated with a second exit angle measured about 0 degrees to 60 degrees from a corresponding tangential direction to the axis of rotation.   
     
     
         6 . The fan apparatus of  claim 5  wherein the second exit angle is smaller than the second inlet angle. 
     
     
         7 . The fan apparatus of  claim 5  wherein the first arrangement of the rotary impeller is associated with the second arrangement of the stationary first plurality of vanes to transform the axial inflow of air into a swirl flow of air with a first increase in air pressure. 
     
     
         8 . The fan apparatus of  claim 7  wherein the first increase in air pressure is proportional to a difference between the second inlet angle and the second exit angle. 
     
     
         9 . The fan apparatus of  claim 7  wherein the first increase in air pressure comprises a 10-to-20% pressure enhancement compared to use the rotary impeller alone. 
     
     
         10 . The fan apparatus of  claim 1  wherein each of the second plurality of vanes comprises an airfoil shape having a third leading edge disposed near the second trailing edge and a corresponding third trailing edge. 
     
     
         11 . The fan apparatus of  claim 10  wherein:
 the third leading edge is associated with a third inlet angle measured about 30 degrees to 60 degrees from a corresponding tangential direction to the axis of rotation;   the third trailing edge is associated with a third exit angle measured about 10 degrees or less from a corresponding tangential direction to the axis of rotation.   
     
     
         12 . The fan apparatus of  claim 10  wherein the third arrangement of the stationary second plurality of vanes is associated with the first arrangement of the rotary impeller to deswirl the swirl flow of air with a second increase of air pressure. 
     
     
         13 . The fan apparatus of  claim 12  wherein the second increase of air pressure comprises a 10-to-20% pressure enhancement compared to use the rotary impeller alone. 
     
     
         14 . A ducted fan apparatus comprising:
 a housing having an interior surface enclosing an interior volume of space;   a first plurality of vanes radially disposed about a first stationary hub and connected to corresponding portions of the interior surface of the housing;   an impeller including a plurality of blades disposed downstream of the first plurality of vanes radially within the interior volume of space for rotary motion about an axis of rotation;   a second plurality of vanes disposed downstream of the impeller, the second plurality of vanes being radially arranged about a second stationary hub and connected to alternative corresponding portions of the interior surface of the housing; and   wherein:
 each of the first plurality of vanes has an airfoil shape including a leading edge arranged with a first inlet angle relative to the axis of rotation and a trailing edge arranged with a first exit angle relative to the axis of rotation, the first exit angle subtended in a direction against direction of rotation of the impeller; 
 each of the plurality of blades has an airfoil shape including a leading edge arranged with a second inlet angle relative to the axis of rotation and a trailing edge arranged with a second exit angle relative to the axis of rotation; 
 each of the second plurality of vanes has an airfoil shape including a leading edge arranged with a third inlet angle relative to the axis of rotation and a trailing edge arranged with a third exit angle relative to the axis of rotation. 
   
     
     
         15 . The ducted fan apparatus of  claim 14  wherein the rotary motion of the impeller comprises operational rotation speeds about 30,000 rpm or higher. 
     
     
         16 . The ducted fan apparatus of  claim 14  wherein the first inlet angle is substantially equal to zero for facilitating an axial inflow of fluid into the ducted fan. 
     
     
         17 . The ducted fan apparatus of  claim 16  wherein the first exit angle is measured between 30 degrees and 60 degrees for redirecting the axial inflow of fluid towards the impeller in the direction against direction of rotation of the impeller. 
     
     
         18 . The ducted fan apparatus of  claim 16  wherein:
 the second inlet angle is between 40 degrees and 80 degrees;   the second exit angle is between 0 degrees and 60 degrees and is smaller than the second inlet angle by a angular difference.   
     
     
         19 . The ducted fan apparatus of  claim 18  wherein the first plurality of vanes and the plurality of blades collectively cause a swirl flow of fluid with a first increase of fluid pressure proportional to the angular difference. 
     
     
         20 . The ducted fan apparatus of  claim 19  wherein the first increase of fluid pressure comprises a 10-20% pressure enhancement compared to use the impeller alone. 
     
     
         21 . The ducted fan apparatus of  claim 19  wherein:
 the third inlet angle is between 30 degrees and 60 degrees;   the third exit angle is substantially equal to zero for diffusing an outflow of air substantially along the axis of rotation.   
     
     
         22 . The ducted fan apparatus of  claim 19  wherein the plurality of blades and the second plurality of vanes collectively deswirl the swirl flow of fluid by converting rotary kinetic energy into pressure and cause a second increase of fluid pressure. 
     
     
         23 . The ducted fan apparatus of  claim 22  wherein the second increase of fluid pressure comprises a 10-20% pressure enhancement compared to use the impeller alone. 
     
     
         24 . The ducted fan apparatus of  claim 14  wherein the first stationary hub is a rounded cone shape for facilitating the redirection of the axial inflow of fluid towards the rotary impeller. 
     
     
         25 . The ducted fan apparatus of  claim 14  wherein the second stationary hub is a housing of a control board for the impeller. 
     
     
         26 . An apparatus for processing fluid flow, the apparatus comprising:
 a ducted housing including a first section and a second section, the first section being mounted with the second section;   a set of blades disposed within the ducted housing, the set of blades consisting a first plurality of stationary vanes, a plurality of rotary blades, and a second plurality of stationary vanes, the first plurality of stationary vanes disposed within the first section upstream of the plurality of rotary blades, the second plurality of stationary vanes disposed downstream of the plurality of rotary blades within the second section;   wherein:
 the plurality of rotary blades are radially arranged in a first arrangement about a rotor having an axis of rotation; 
 the first plurality of stationary vanes are radially arranged in a second arrangement about the axis of rotation; 
 the second plurality of stationary vanes are radially arranged in a third arrangement about the axis of rotation; 
 the second arrangement is associated with the first arrangement to guide an axial inflow of fluid to a direction against direction of rotation of the rotary blades; 
 the third arrangement is associated with the first arrangement to generate an axial outflow of fluid with an enhanced fluid pressure over the axial inflow of fluid. 
   
     
     
         27 . The apparatus of  claim 26  wherein the plurality of rotary blades radially arranged in a first arrangement about a rotor comprises an impeller capable of rotating with speeds of 30,000 rpm or higher. 
     
     
         28 . The apparatus of  claim 26  wherein:
 the second arrangement comprises a first inlet angle and a first exit angle for each of the first plurality of stationary vanes;   the first arrangement comprises a second inlet angle and a second exit angle for each of the plurality of rotary blades;   the third arrangement comprises a third inlet angle and a third exit angle for each of the second plurality of stationary vanes.   
     
     
         29 . The apparatus of  claim 28  wherein:
 the first inlet angle is measured about 10 degrees or less from a leading-edge tangential direction to the axis of rotation;   the first exit angle is measured about 30 degrees to 60 degrees from a corresponding trailing-edge tangential direction to the axis of rotation;   the second inlet angle is measured about 40 degrees to 80 degrees, depending on the first exit angle, from a leading-edge tangential direction to the axis of rotation;   the second exit angle is measured about 0 degrees to 60 degrees from a corresponding trailing-edge tangential direction to the axis of rotation;   the third inlet angle is a measured about 30 degrees to 60 degrees from a leading-edge tangential direction to the axis of rotation;   the third exit angle is a substantially equal to zero from a corresponding trailing-edge tangential direction to the axis of rotation.   
     
     
         30 . The apparatus of  claim 29  wherein the second inlet angle is larger than the second exit angle so that the plurality of rotary blades cause a first increase of fluid pressure proportional to a difference between the second inlet angle and the second exit angle. 
     
     
         31 . The apparatus of  claim 29  wherein combination of the second arrangement and the first arrangement collectively causes a second increase of fluid pressure, the second increase is 10-20% greater than the first increase. 
     
     
         32 . The apparatus of  claim 29  wherein combination of the third arrangement and the first arrangement collectively causes a third increase of fluid pressure, the third increase is 10-20% greater than the first increase.