DIRECT METERING USING A VARIABLE DISPLACEMENT VANE PUMP

摘要

A direct metering architecture is provided having a metering pump and a servo pump wherein the metering and servo pumps are driven by an engine shaft by way of a gearbox transmission. The system reduces wasted horsepower previously occurring with oversized fixed displacement pumps, reduces instances of engine flameout and reduces the amount of heat added to fuel which ultimately improves engine oil cooling.

主权项

1. A gas turbine engine fuel supply system with direct metering architecture, comprising:
an engine power takeoff shaft providing a mechanical power input to a gearbox; said gearbox providing at least one driving output to a variable displacement metering pump and a servo pump; said variable displacement metering pump which meters an engine burn flow of fuel engine burn; said servo pump providing a servo flow of fuel necessary for actuation of at least one of a valve or actuator; wherein said servo flow of fuel and said engine burn flow of fuel are isolated from each other and interactions between said servo flow of fuel and said engine burn flow of fuel are reduced.