FUEL DELIVERY AND CONTROL SYSTEM INCLUDING A VARIABLE DISPLACEMENT ACTUATION PUMP SUPPLEMENTING A FIXED DISPLACEMENT MAIN PUMP

摘要

A fuel delivery and control system is provided including a dual pump fluid circuit configuration comprising a fixed positive displacement pump sized to supply the main engine burn flow ranging from above windmill through cruise and a variable displacement pump sized to supply fluid to engine actuators, valves and other hydraulically operated engine components with a pump flow sharing system interconnecting the two pumps. The combined flow from the two pumps is sufficient to meet the engine flow demand for windmill relight and maximum flow conditions. During cruise or normal operating conditions, the pumps operate in completely isolated flow circuits, minimizing recirculation and therefore heat input into the fuel supply system.