Pulse stimulation tool and method of use

Abstract

A downhole pulse stimulation tool for use within a production or injection string including a tubing string, a rotating or reciprocating rod string and a downhole pump. The tool is formed by a resonance chamber defined by a cylindrical outer tubular member connected to the tubing string and having pulse emitting openings, a pulse generator rotatably disposed within the resonance chamber having longitudinal channels and defining pulse generating openings, wherein the pulse generating openings periodically align with the pulse emitting openings as the pulse generator rotates or reciprocates within the resonance chamber.

1 . A downhole pulse stimulation tool for use within a production or injection string including a tubing string, a rotating rod string and a downhole pump, the tool comprising:
 (a) a resonance chamber defined by a cylindrical outer tubular member defining at least one pulse emitting opening, the outer tubular member connecting to the tubing string;   (b) a pulse generator rotatably disposed within the resonance chamber, the pulse generator having a longitudinal channel and defining a least one pulse generating opening, wherein the at least one pulse generating opening periodically aligns with the pulse emitting opening as the pulse generator rotates with the resonance chamber to provide fluid communication from the longitudinal channel to outside the outer tubular member;   (c) wherein the pulse generator is directly or indirectly rotated by the rod string.   
     
     
         2 . The tool of  claim 1  wherein the pulse generator defines at least two longitudinal channels, substantially parallel to the axis of rotation, wherein the at least one pulse generating opening opens into one of the longitudinal channels. 
     
     
         3 . The tool of  claim 2  wherein the pulse generator defines five or more longitudinal channels. 
     
     
         4 . The tool of  claim 2  wherein the pulse generator is directly rotated by the rod string. 
     
     
         5 . The tool of  claim 1  wherein the pulse generator comprises a plurality of curved channels, wherein fluid flow through the curved channels causes rotation of the pulse generator. 
     
     
         6 . The tool of  claim 5  wherein the plurality of curved channels are helically disposed about the axis of rotation. 
     
     
         7 . The tool of  claim 6  wherein the pulse generator defines an upper pulse generating opening and a lower pulse generating opening, wherein both the upper and lower pulse generating openings open into the same helical channel. 
     
     
         8 . The tool of  claim 6  wherein the plurality of helical channels make substantially one or more rotations about the axis of rotation. 
     
     
         9 . The tool of  claim 2  wherein the longitudinal channels comprise slots extending radially outward from a central portion to a periphery of the pulse generator. 
     
     
         10 . The tool of  claim 9  wherein the slots are configured in a cruciform configuration. 
     
     
         11 . The tool of  claim 9  further comprising a secondary outlet comprising a bottom plate defining openings which come into and out of alignment with the slots as the pulse generator rotates. 
     
     
         12 . A downhole pulse stimulation tool for use within a production or injection string including a tubing string, a reciprocating rod string and downhole pump, the tool comprising:
 (a) a resonance chamber defined by a cylindrical outer tubular member defining at least one pulse emitting opening, the outer tubular member connecting to the tubing string;   (b) a pulse generator slidingly disposed within the resonance chamber, the pulse generator having a central bore and defining a least one pulse generating opening, wherein the at least one pulse generating opening periodically aligns with the pulse emitting opening as the pulse generator reciprocates with the resonance chamber to provide fluid communication between the central bore and the exterior of the outer tubular member;   (c) wherein the pulse generator is directly or indirectly reciprocated by the rod string.