Efficiency improvements for liquid ring pumps

Abstract

The present invention is directed to a textured surface that provides for drag reduction, and therefore efficiency improvements in a liquid ring pump. At least a portion of the surfaces of the pump that contact fluid therein the pump are textured to control boundary layer separation. The texture can be a plurality of dimples are defined therein the surface. The dimples have a predetermined shape, size, density and pattern.

1 . A method for reducing frictional losses in a liquid ring pump, comprising:
 providing a liquid ring pump having at least one interior surface exposed to a fluid; and   defining a texture on at least a portion of the at least one interior surface, wherein the texture is configured to reduce drag as the fluid passes over the texture.   
     
     
         2 . The method of  claim 1 , wherein the texture is a plurality of dimples. 
     
     
         3 . The method of  claim 2 , wherein at least one dimple of the plurality of dimples is substantially spherical in shape. 
     
     
         4 . The method of  claim 3 , wherein the at least one dimple has a diameter of about 0.185 inches and a depth of about 0.038 inches. 
     
     
         5 . The method of  claim 2 , wherein the plurality of dimples are arranged to form an array having a plurality of substantially linear rows of dimples. 
     
     
         6 . The method of  claim 5 , wherein the dimples of successive adjacent rows are substantially offset in a direction perpendicular to the linear rows. 
     
     
         7 . The method of  claim 5 , wherein the dimples of successive adjacent rows are substantially aligned in a direction perpendicular to the linear rows. 
     
     
         8 . The method of  claim 2 , wherein the plurality of dimples comprise at least a first plurality of dimples and a second plurality of dimples, wherein the first plurality of dimples is substantially spherical in shape, and wherein the second plurality of dimples is not spherical in shape. 
     
     
         9 . The method of  claim 2 , wherein the plurality of dimples comprises at least a first plurality of dimples and a second plurality of dimples, wherein the first plurality of dimples is a first shape, and wherein the second plurality of dimples is a second shape. 
     
     
         10 . The method of  claim 2 , wherein the plurality of dimples comprises at least a first plurality of dimples and a second plurality of dimples, wherein the first plurality of dimples is a first size, and wherein the second plurality of dimples is a second size. 
     
     
         11 . The method of  claim 1 , wherein the texture defined therein at least a portion of the at least one interior surface reduces drag by controlling separation of a fluid boundary layer. 
     
     
         12 . The method of  claim 1 , wherein the liquid ring pump comprises:
 a stationary housing having an annular peripheral wall;   a drive shaft rotatably mounted therein the stationary housing, wherein the drive shaft has a longitudinal axis and wherein the drive shaft extends through the rear plate; and   a rotor comprising an annular rotor hub, a plurality of blades extending radially outward from the rotor hub in planes substantially parallel to the longitudinal axis of the drive shaft, and a rear shroud extending radially outward from the rotor hub in a plane substantially perpendicular to the longitudinal axis of drive shaft, wherein in the annular rotor hub is mounted the to the drive shaft therein the stationary housing.   
     
     
         13 . The method of  claim 12 , wherein the texture is defined therein at least a portion of the inner periphery of the annular peripheral wall. 
     
     
         14 . The method of  claim 12 , wherein the texture is defined therein at least a portion of the plurality of blades of the rotor. 
     
     
         15 . The method of  claim 12 , wherein the liquid ring pump further comprises an annular liner having a cylindrical body disposed therein the inner periphery of the housing, and wherein the texture is defined therein at least a portion of the annular liner. 
     
     
         16 . The method of  claim 15 , wherein the annular liner is a rotating annular liner. 
     
     
         17 . A liquid ring pump, comprising:
 a stationary housing having an annular peripheral wall;   a drive shaft rotatably mounted therein the stationary housing, wherein the drive shaft has a longitudinal axis; and   a rotor comprising an annular rotor hub, a plurality of blades extending radially outward from the rotor hub in planes substantially parallel to the longitudinal axis of the drive shaft, and a rear shroud extending radially outward from the rotor hub in a plane substantially perpendicular to the longitudinal axis of drive shaft, wherein in the annular rotor hub is mounted the to the drive shaft therein the stationary housing; and   means for reducing frictional losses within the pump.   
     
     
         18 . The liquid ring pump of  claim 17 , wherein the means for reducing frictional losses therein the pump comprises defining a texture therein at least a portion of at least one of the annular peripheral wall, a rotating sleeve positioned in the stationary housing, the annular rotor hub, and at least one blade of the plurality of blades. 
     
     
         19 . The liquid ring pump of  claim 18 , wherein the texture is a plurality of dimples. 
     
     
         20 . The method of  claim 19 , wherein at least one dimple of the plurality of dimples is substantially spherical in shape. 
     
     
         21 . The method of  claim 19 , wherein the plurality of dimples are arranged to form an array having a plurality of substantially linear rows of dimples. 
     
     
         22 . The method of  claim 19 , wherein the plurality of dimples are arranged in a pattern of dimples. 
     
     
         23 . The method of  claim 19 , wherein at least one dimple of the plurality of dimples is substantially polyhedral in shape. 
     
     
         24 . A method for improving efficiency of a liquid ring pump, comprising:
 providing a liquid ring pump comprising:
 a stationary housing having an annular peripheral wall; 
 a drive shaft rotatably mounted therein the stationary housing, wherein the drive shaft has a longitudinal axis; and 
 a rotor comprising an annular rotor hub, and a plurality of blades extending radially outward from the hub in planes substantially parallel to the longitudinal axis of the drive shaft, wherein in the annular rotor hub is mounted the to the drive shaft therein the stationary housing, and 
   defining a texture on at least portions of at least one of the rotor hub, the blades of the rotor, and an inner periphery of the annular peripheral wall, wherein the texture is configured to reduce drag as a fluid passes over the texture.