Disc pump

Abstract

A pump is disclosed having one or more rotating discs within a housing. The discs have a plurality of relatively small surface perturbations covering at least half of one side of their surface. The perturbations may be recessed or raised. In operation, a boundary layer is formed near the surface of the rotating discs. The fluid within the pump flows in a circular and outward direction, thus moving fluid from a central coaxial inlet to an outlet located at the peripheral wall of the housing. The surface perturbations produce turbulence within the boundary layer during operation. The pump is suitable for pumping liquids with entrained gases, liquids with entrained solids, liquids with both gases and solids, and thick liquids.

1 . A pump comprising,
 a. a generally cylindrical housing formed by a front wall, a back wall, and a peripheral wall, wherein the front wall has a central, coaxial inlet and the peripheral wall has an outlet;   b. a disc positioned within the housing, one side of the disc having a plurality of surface perturbations, wherein each surface perturbation covers less than 5% of the surface area of the side of the disc and the plurality of surface perturbations collectively cover at least 50% of the surface area of the side of the disc; and,   c. a rotational drive member extending through the back wall of the housing and connected to the disc.   
     
     
         2 . The pump of  claim 1 , wherein the surface perturbations are recessed. 
     
     
         3 . The pump of  claim 2 , wherein the depth of the recessed surface perturbations is no more than 50% of the thickness of the disc. 
     
     
         4 . The pump of  claim 2 , wherein the recessed surface perturbations are generally hemispherical. 
     
     
         5 . The pump of  claim 2 , wherein the recessed surface perturbations are generally cylindrical. 
     
     
         6 . The pump of  claim 2 , wherein the recessed surface perturbations are generally conical. 
     
     
         7 . The pump of  claim 1 , wherein the disc further comprises a second side having a plurality of surface perturbations, wherein each surface perturbation covers less than 5% of the surface area of the second side of the disc and the plurality of surface perturbations collectively cover at least 50% of the surface area of the second side of the disc. 
     
     
         8 . The pump of  claim 1 , wherein the plurality of surface perturbations includes both raised and recessed perturbations. 
     
     
         9 . The pump of  claim 1 , wherein the surface perturbations are holes extending fully through the disc. 
     
     
         10 . The pump of  claim 1 , wherein the surface perturbations are raised. 
     
     
         11 . The pump of  claim 10 , wherein the raised surface perturbations are generally hemispherical. 
     
     
         12 . The pump of  claim 10 , wherein the raised surface perturbations are generally cylindrical. 
     
     
         13 . The pump of  claim 10 , wherein the raised surface perturbations extend outward from the surface of the disc a distance no greater than 50% of the thickness of the disc. 
     
     
         14 . The pump of  claim 1 , wherein the surface perturbations cover at least 70% of the surface area of one side of the disc. 
     
     
         15 . The pump of  claim 1 , further comprising a second disc operatively connected to the first disc and having a plurality of surface perturbations on one side, wherein each surface perturbation covers less than 5% of the surface area of one side of the second disc and the plurality of surface perturbation collectively cover at least 50% of the surface area of one side of the second disc. 
     
     
         16 . A pump comprising,
 a. a generally cylindrical housing formed by a front wall, a back wall, and a peripheral wall, wherein the front wall has a central, coaxial inlet and the peripheral wall has an outlet;   b. one or more pairs of discs positioned within the housing, wherein each disc has a plurality of surface perturbations on one side of the disc, each surface perturbation covering less than 5% of the surface area of one side of the disc, and the plurality of surface perturbations collectively covering at least 50% of the surface area of one side of the disc; and,   c. a rotational drive shaft extending through a central, coaxial opening in the back wall of the housing and connected to at least one disc.   
     
     
         17 . A pump comprising,
 a. a generally cylindrical housing formed by a front wall, a back wall, and a peripheral wall, wherein the front wall has a central, coaxial inlet and the peripheral wall has an outlet;   b. a disc positioned within the housing, one side of the disc having a plurality of dimples, wherein each dimple covers less than 5% of the surface area of the side of the disc, and the plurality of dimples collectively cover at least 50% of the surface area of the side of the disc; and,   c. a rotational drive member extending through the back wall of the housing and connected to the disc.   
     
     
         18 . The pump of  claim 17 , wherein the depth of the dimples is approximately 50% of the thickness of the disc. 
     
     
         19 . The pump of  claim 17 , wherein the dimples are generally hemispherical. 
     
     
         20 . The pump of  claim 17 , wherein the dimples are generally cylindrical. 
     
     
         21 . The pump of  claim 17 , wherein the dimples are generally conical. 
     
     
         22 . A pump impellor, comprising:
 a. a cylinder having a diameter and a thickness, wherein the diameter is at least five times larger than the thickness, the cylinder further having,
 i. a first circular surface configured for attachment to a rotational drive shaft; and, 
 ii. a second circular surface having a plurality of surface perturbations, wherein each surface perturbation covers less than 5% of the second circular surface, and the plurality of surface perturbations collectively cover at least 50% of the second circular surface.