Series Plus Parallel Metering Pressure Regulation System for a Thermal Efficient Fuel Metering System
AssigneeWoodward, Inc.
InventorCarthel C. Baker
Life of this patent
Estimating the term…
Abstract
An engine fuel system and methods are provided. The engine fuel system includes a supply arrangement for providing an outlet flow of fuel to a bypass metering arrangement. The bypass metering arrangement in turn provides a metered flow of fuel to a parallel metering system including a primary regulated circuit and one or more secondary metering circuits. The bypass metering arrangement is operable to maintain a substantially constant pressure differential across a fuel metering valve thereof, as well as provide the metered flow of fuel in response to downstream pressure demands of the parallel metering system.
Claims20
An engine fuel system, comprising:
- a supply arrangement including at least one pump for providing an outlet flow of fuel;
- a bypass metering system in fluid communication with the supply arrangement and including a fuel metering valve and a bypass regulator in fluid communication with an inlet of the fuel metering valve and an inlet of the at least one pump, the bypass regulator operable to bypass at least a portion of the outlet flow of fuel from the at least one pump back to the inlet of the at least one pump;
- a parallel metering system including a primary regulated circuit and at least two secondary metering circuits arranged in parallel with the primary regulated circuit, the parallel metering system in fluid communication with the bypass metering system such that it receives a metered flow of fuel from the fuel metering valve of the bypass metering system;
- and
- wherein the primary regulated circuit includes a primary pressure regulator that is operably connected to the primary regulated circuit and the at least two secondary metering circuits to detect a pressure in each of the primary and at least two secondary metering circuits.
An engine fuel system, comprising:
- a supply arrangement including at least one pump for providing an outlet flow of fuel;
- a bypass metering system in fluid communication with the supply arrangement and including a fuel metering valve and a bypass regulator in fluid communication with an inlet of the fuel metering valve and an inlet of the at least one pump and operably connected to an outlet of the fuel metering valve to detect a pressure at the outlet of the fuel metering valve, the bypass regulator operable to maintain a substantially constant pressure differential across the fuel metering valve;
- a parallel metering system including a primary regulated circuit and at least two secondary metering circuits arranged in parallel with the primary regulated circuit, the parallel metering system in fluid communication with the bypass metering system such that it receives a metered flow of fuel from the fuel metering valve of the bypass metering system;
- and
- wherein the primary regulated circuit includes a primary pressure regulator that is operably connected to the primary regulated circuit and the at least two secondary metering circuits to detect a pressure in each of the primary and at least two secondary metering circuits, the primary pressure regulator operable to set an inlet side pressure of the primary pressure regulator at least as high as a highest one of the detected pressures of the primary and at least two secondary metering circuits, plus a regulated pressure value of the primary pressure regulator.
A method for managing a flow of fuel in an engine fuel system having a parallel metering system that includes a primary regulated circuit and at least one secondary metering circuit, the method comprising the steps of:
- providing a metered flow of fuel to the parallel metering circuit, the metered flow of fuel divided between the primary regulated circuit and at least two secondary metering circuits;
- detecting, with a primary pressure regulator of the primary regulated circuit, a downstream pressure of the primary regulated circuit and a downstream pressure of the at least two secondary metering circuits;
- adjusting an inlet side pressure of the primary pressure regulator to be at least as high as a highest one of the detected downstream pressures of the primary regulated circuit and the at least two secondary metering circuits, plus a regulated pressure value of the primary pressure regulator;
- detecting, with a bypass regulator of a bypass metering system in fluid communication with the parallel metering system, the adjusted inlet side pressure of the primary pressure regulator;
- and
- adjusting an inlet pressure of a flow of fuel to a fuel metering valve of the bypass metering system using the bypass regulator to maintain a substantially constant pressure differential across the fuel metering valve.
Dependencies are inferred from the claim text.