Abstract: A movable flow controller is interposed in a fluid flow path. The flow controller includes an elongate groove having a first end and a second end. The groove preferably is sized and shaped so that a cross-sectional area of the groove changes along its length from the first end to the second end, and terminates in a hole through the flow controller. In operation, a portion of the groove is aligned with an inlet of the flow path on a first side of the controller, and the hole is in communication with an outlet of the flow path on a second side of the controller. Moving the flow controller relative to the flow path input varies the minimum cross-sectional area of the flow path through the controller and thus selectively limits fluid flow through the controller.

Abstract: A movable flow controller is interposed in a fluid flow path. The flow controller includes an elongate groove having a first end and a second end. The groove preferably is sized and shaped so that a cross-sectional area of the groove changes along its length from the first end to the second end, and terminates in a hole through the flow controller. In operation, a portion of the groove is aligned with an inlet of the flow path on a first side of the controller, and the hole is in communication with an outlet of the flow path on a second side of the controller. Moving the flow controller relative to the flow path input varies the minimum cross-sectional area of the flow path through the controller and thus selectively limits fluid flow through the controller.