High volume axial flow electric submersible pump (ESP) pump stage

A method of assembling an electric submersible pump (ESP) assembly, comprising:

• coupling an uphole end of an electric motor to a downhole end of a seal section and coupling an uphole end of a first drive shaft of the electric motor to a downhole end of a second drive shaft of the seal section;
• lowering the electric motor at least partly into a wellbore;
• coupling an uphole end of the seal section to a downhole end of a housing and coupling an uphole end of the second drive shaft of the seal section to a downhole end of a third drive shaft disposed at least partly within the housing, wherein a centrifugal pump stage is disposed inside of the housing, wherein the centrifugal pump stage comprises an impeller coupled to the third drive shaft and a diffuser retained by the housing, wherein the impeller defines a plurality of flow passages between an impeller hub and an impeller shroud and a plurality of impeller vanes attached between the impeller hub and the impeller shroud, wherein an interior of the impeller shroud is a straight-walled cylindrical shape along its entire axial extension, wherein a surface of each impeller vane angles downhole from an attachment point at the impeller hub to an attachment point at the impeller shroud, wherein a leading edge of each of the impeller vanes is cupped downhole so that a middle point along the leading edge of each of the impeller vanes departs downhole from a line extending from a first point where the leading edge attaches to the impeller hub and to a second point where the leading edge attaches to the impeller shroud by between 4 mm and 15 mm, wherein the hub defines an inner barrel opening that surrounds the third drive shaft, wherein the diffuser defines a plurality of flow passages between a diffuser hub and a diffuser shroud and a plurality of diffuser vanes attached between the diffuser hub and the diffuser shroud, and wherein an interior of the diffuser shroud is a straight-walled cylindrical shape along its entire axial extension;
• lowering the electric motor and seal section at least partly into the wellbore;
• coupling an uphole end of the housing directly or indirectly to a production tubing;
• and
• running the electric motor, the seal section, the housing, and the production tubing into the wellbore.

A method of lifting fluid in a wellbore, comprising:

• running an electric submersible pump (ESP) assembly into the wellbore, wherein the ESP assembly comprises
• an electric motor having a first drive shaft,
• a seal section coupled at a downhole end to an uphole end of the electric motor and having a second drive shaft that is coupled to the first drive shaft,
• a third drive shaft that is coupled to the second drive shaft, and
• a centrifugal pump assembly comprising a plurality of centrifugal pump stages, wherein each centrifugal pump stage comprises an impeller coupled to the third drive shaft and a diffuser retained by a housing of the centrifugal pump assembly, wherein the impeller defines a plurality of flow passages between an impeller hub and an impeller shroud and a plurality of impeller vanes attached between the impeller hub and the impeller shroud, wherein an interior of the impeller shroud is a straight-walled cylindrical shape along its entire axial extension, wherein a surface of each impeller vane angles downhole from an attachment point at the impeller hub to an attachment point at the impeller shroud, wherein a leading edge of each of the impeller vanes is cupped downhole so that a middle point along the leading edge of each of the impeller vanes departs downhole from a line extending from a first point where the leading edge attaches to the impeller hub and to a second point where the leading edge attaches to the impeller shroud by between 4 mm and 15 mm, wherein the hub defines an inner barrel opening that surrounds the third drive shaft, wherein the diffuser defines a plurality of flow passages between a diffuser hub and a diffuser shroud and a plurality of diffuser vanes attached between the diffuser hub and the diffuser shroud, and wherein an interior of the diffuser shroud is a straight-walled cylindrical shape along its entire axial extension;
• providing electric power to the ESP assembly;
• receiving a mixture of gas phase fluid and of liquid phase fluid into an inlet of the centrifugal pump assembly;
• homogenizing the mixture of gas phase fluid and of liquid phase fluid by the plurality of centrifugal pump stages;
• and
• lifting the homogenized mixture of gas phase fluid and of liquid phase fluid by the centrifugal pump assembly in the wellbore.