REGENERATIVE PUMPING ELEMENT START STAGE FOR HIGH-SPEED CENTRIFUGAL PUMP

摘要

A pumping system for an aircraft engine includes a centrifugal pump and a regenerative start stage that is selectively decoupled from the system upon sufficient pressure being provided by the centrifugal pump. A regulator interposed between the centrifugal pump and the regenerative start stage reduces flow to the start stage in response to increasing output of the centrifugal pump. An ejector removes fuel from the regenerative start stage once the regulator valve is closed, and likewise a check valve is interposed between the outlet of the regenerative start stage and the outlet of the centrifugal pump. This check valve isolates the regenerative pump from the remainder of the system and scavenges or evacuates the fuel from the regenerative pump circuit.