The inventive technology, in particular embodiments thereof, may be described as an apparatus (e.g., a pump) that imparts work to and redirects a fluid, and that features an impeller configured to contact and redirect an impeller inflow along a toroidal flowpath to generate an impeller discharge that has both axial and tangential velocity components, where the axial velocity component is substantially 180 degrees relative to a direction of an impeller inflow, in a meridional plane, the apparatus also featuring a diffuser having a diffuser axis that is aligned with an impeller axis of rotation, the diffuser featuring a diffuser outlet annular radial size that is greater than a diffuser inlet annular radial size; and/or curved diffuser vanes established as part of the diffuser, that redirect the impeller discharge so as to reduce the tangential velocity components.

The inventive technology, in particular embodiments thereof, may be described as an apparatus (e.g., a pump) that imparts work to and redirects a fluid, and that features an impeller configured to contact and redirect an impeller inflow along a toroidal flowpath to generate an impeller discharge that has both axial and tangential velocity components, where the axial velocity component is substantially 180 degrees relative to a direction of an impeller inflow, in a meridional plane, the apparatus also featuring a diffuser having a diffuser axis that is aligned with an impeller axis of rotation, the diffuser featuring a diffuser outlet annular radial size that is greater than a diffuser inlet annular radial size; and/or curved diffuser vanes established as part of the diffuser, that redirect the impeller discharge so as to reduce the tangential velocity components.

A downhole system includes a drill string having a drilling fluid flow channel and at least one turbine alternator deployed in the flow channel. The turbine alternator is configured to convert flowing drilling fluid to electrical power. A voltage bus is configured to receive electrical power from the turbine alternator and at least one electrical motor is configured to receive electrical power from the voltage bus. An electronic controller is configured to provide active control of the turbine alternator via processing a desired speed of the electrical motor to generate a desired torque current and feeding the desired torque current forward to the turbine alternator. The turbine alternator is responsive to the desired torque current such that it modifies the electrical power provided to the voltage bus in response to the desired torque.

A turbine current generator includes a hollow bearing cylinder to be engaged inside a pipe or duct for the transit of a fluid, in particular a fluid transit duct deriving from the drilling or exploration of an oil field; a hollow rotating cylinder rotatably and coaxially engaged inside the bearing cylinder and defining a respective transit cylindrical chamber for a fluid. The bearing and rotating cylinders defining at least a cylindrical gap; one or more magnetic or electromagnetic components (6)-operatively engaged to the bearing cylinder and/or to the rotating cylinder to generate at least one electric current during the rotation of the rotating cylinder inside the bearing cylinder; an impeller or impellers arranged in the chamber of the rotating cylinder according to positions aligned along a longitudinal axis of the latter, the impellers engaged inside the rotating cylinder to rotate integrally with the latter upon the action of a fluid.

A turbine current generator includes a hollow bearing cylinder to be engaged inside a pipe or duct for the transit of a fluid, in particular a fluid transit duct deriving from the drilling or exploration of an oil field; a hollow rotating cylinder rotatably and coaxially engaged inside the bearing cylinder and defining a respective transit cylindrical chamber for a fluid. The bearing and rotating cylinders defining at least a cylindrical gap; one or more magnetic or electromagnetic components (6)-operatively engaged to the bearing cylinder and/or to the rotating cylinder to generate at least one electric current during the rotation of the rotating cylinder inside the bearing cylinder; an impeller or impellers arranged in the chamber of the rotating cylinder according to positions aligned along a longitudinal axis of the latter, the impellers engaged inside the rotating cylinder to rotate integrally with the latter upon the action of a fluid.

A disclosed mud motor includes a rotor head, a motor block, a hollow rotor, an inlet shaft, and an outlet shaft. In the operation of one embodiment, a pressurized drilling mud enters the rotor head through the inlet shaft. Some or all of the drilling mud is directed through an included inlet passage onto pistons which are included in the motor block and disposed concentrically around the outlet shaft. A downward action of the pistons resulting from the drilling mud causes an included power plate to rotate. Rotation of the power plate causes the hollow rotor and the rotor head to also rotate. The hollow rotor may be attached to a drilling implement. Rotation of the power plate also causes some or all of the drilling mud directed onto the pistons to be discharged into the outlet shaft through an included discharge passage. During the operation of one embodiment of the mud motor, the pistons do not rotate around the outlet shaft, but instead remain substantially in their original concentric alignment.

A disclosed mud motor includes a rotor head, a motor block, a hollow rotor, an inlet shaft, and an outlet shaft. In the operation of one embodiment, a pressurized drilling mud enters the rotor head through the inlet shaft. Some or all of the drilling mud is directed through an included inlet passage onto pistons which are included in the motor block and disposed concentrically around the outlet shaft. A downward action of the pistons resulting from the drilling mud causes an included power plate to rotate. Rotation of the power plate causes the hollow rotor and the rotor head to also rotate. The hollow rotor may be attached to a drilling implement. Rotation of the power plate also causes some or all of the drilling mud directed onto the pistons to be discharged into the outlet shaft through an included discharge passage. During the operation of one embodiment of the mud motor, the pistons do not rotate around the outlet shaft, but instead remain substantially in their original concentric alignment.

An apparatus for extending the operational flow rate range of a turbine is described herein. Two or more removable sleeves may be used to change the cross-sectional area of a turbine. Each removable sleeve may define or eliminate the stator gap between a stator blade tip and an inner wall of the removable sleeve and a rotor gap between a rotor blade tip and an inner wall of the removable sleeve. A movable sleeve may be disposed in the turbine and may move between a first position and a second position in response to changes in the pressure differential across the turbine. The movable sleeve may define or eliminate a stator gap between a stator blade tip and the inner conical surface of the sleeve or a hub of the turbine and a rotor gap between a rotor blade tip and the inner conical surface of the sleeve.

An apparatus for extending the operational flow rate range of a turbine is described herein. Two or more removable sleeves may be used to change the cross-sectional area of a turbine. Each removable sleeve may define or eliminate the stator gap between a stator blade tip and an inner wall of the removable sleeve and a rotor gap between a rotor blade tip and an inner wall of the removable sleeve. A movable sleeve may be disposed in the turbine and may move between a first position and a second position in response to changes in the pressure differential across the turbine. The movable sleeve may define or eliminate a stator gap between a stator blade tip and the inner conical surface of the sleeve or a hub of the turbine and a rotor gap between a rotor blade tip and the inner conical surface of the sleeve.

Methods of configuring a surface of a component exposed to fluid flow are disclosed. A first method includes forming a plurality of protrusions on a surface, the plurality of protrusions separated by a plurality of channels, and depositing a coating on the surface to increase a coefficient of friction of the surface, the coating formed of a diamond-like carbon and having a wrinkled texture. A second method includes forming a plurality of protrusions on a surface, the plurality of protrusions separated by a plurality of channels, and forming a plurality of nanotubes on the surface.