Patent ID: 8514657

Claim:
A downhole tool comprising: a tool body aligned longitudinally along a centerline of the tool, the tool body comprising at least one aperture therethrough that is operable to pass a fluid to an exterior of the body; a stator fixed relative to the tool body and comprising at least one fluid flow restriction that is operable to pass at least a portion of the fluid from an interior of the stator to the exterior of the body at an adjustable flow rate, the stator comprising an inner radial surface; and a rotor disposed within the tool body and rotatable relative to the stator, the rotor comprising at least one exhaust port selectively aligned with at least one aperture through the tool body by rotation of the rotor relative to the stator, the exhaust port operable to pass at least a portion of the fluid from an interior of the rotor to the aperture and to the exterior of the body when aligned with the aperture, the rotor comprising an inner radial surface that is adjacent and substantially parallel to the outer radial surface of the stator, the inner and outer radial surfaces comprising a fluid interface between the rotor and the stator.