DOC AIRBUS | AMM A320FFUEL DISTRIBUTION SYSTEM - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
Engine Fuel and Control System - (Fuel Nozzles)(1) The fuel distribution system supplies calculated, filtered fuel to the engine at the pressure and flow rate necessary to meet all engine requirements while in operation. The fuel is also heated to prevent ice accumulation.
(2) The system supplies calculated fuel to the fuel injectors for combustion and pressurized fuel to the engine component actuators for stable pressure.
2. Component Location
** ON A/C NOT FOR ALL - Fuel nozzles: Find and mark the notch located at the top 12 o'clock position on the diffuser case.
- The return to tank module is located under the fuel/oil heat exchanger bypass valve at the 5 o'clock position.
- The fuel flow divider is located under the fuel/oil heat exchanger bypass valve at the 5 o'clock position.
- Find the Integrated Fuel Pump and Control (IFPC) attached to the fuel manifold on the top of the main gearbox at the 4 o'clock position.
- The fuel manifold is located at approximately the 4 o'clock position attached to the main gearbox.
- The fuel filter is attached to the fuel manifold on the top of the main gearbox at the 4 o'clock position.
| FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 2005EM | NOZZLE-FUEL | 400 | 73-11-40 | ||
| 4072KS | HARNESS-CORE,WC11 | 400 | 73-11-00 | ||
| 4090KS | FUEL FLOW DIVIDER | 400 | 73-11-03 | ||
| 4360KS | INTEGRATED FUEL PUMP AND CONTROL | 400 | 73-11-00 | ||
3. Component Description
A. The fuel distribution system consists of these components:
(1) Integrated Fuel Pump and Control (IFPC)
(2) Fuel filter
(3) Fuel/oil heat exchanger (includes bypass valve)
(4) Fuel manifold
(5) Fuel nozzles
(6) The IFPC is an electronically controlled unit which uses a dual coil torque motor and solenoids to control fuel flow in relation to the hydro-mechanical valves.
(a) The dual coil torque motor controlled by the Electronic Engine Control (EEC) positions the valve that measures fuel.
(b) The meter valve position is sent back to the EEC by a dual coil Linear Variable Differential Transformer (LVDT).
(c) There is also a fuel temperature sensor installed on the IFPC.
B. Integrated Fuel Pump and Control (IFPC)
(1) The IFPC consists of a fuel pump and control.
(a) The fuel pump supplies low pressure boost stage fuel to the fuel/oil heat exchanger and fuel filter and then to the gear stage inlet port of the fuel pump. The gear stage pump sends high-pressure fuel through a valve that measures fuel in the IFPC.
(b) The boost stage is a centrifugal pump and the main stage is a gear-type positive displacement pump.
(c) The fuel pump is attached with bolts to the fuel manifold on the top right of the main gearbox.
(2) The IFPC supplies measured fuel flow to the engine as scheduled by the EEC.
(3) The IFPC is an electronically controlled unit which uses a dual coil torque motor and solenoids to control fuel flow in relation to the hydro-mechanical valves.
(a) The dual coil torque motor controlled by the EEC positions the valve that measures fuel.
(b) The meter valve position is sent back to the EEC by a dual coil Linear Variable Differential Transformer (LVDT).
(4) Two solenoids in the IFPC can be used to operate the valve that meters fuel. They are the overspeed/shutdown solenoid and the pressure equalization solenoid.
(a) The EEC directs the overspeed/shutdown solenoid to position the Minimum Pressurizing and Shut Off Valve (MPSOV) to the shut off position.
(b) The dual coil shut off solenoid is directed by the EEC to open the equalization bypass valve to make equal pressure in the primary and secondary fuel manifolds downstream of the flow divider valve. This will make sure that there is an equal fuel-to-air ratio in the combustor.
C. Fuel Filter
(1) The main fuel filter element is used to remove solid impurities from the pressurized fuel sent from the IFPC.
(2) The filtered fuel goes from the main fuel filter to the main fuel pump contained within the IFPC and then splits in two directions - to the flow divider valve and fuel nozzles and to the turbine Active Clearance Control (ACC), High Pressure Compressor (HPC), Low Pressure Compressor (LPC) and 2.5 bleed actuators.
(3) The main fuel filter element is in the main fuel filter cover installed on the forward side of the fuel manifold near the 4 o'clock engine position.
(4) An isolated fuel filter bypass valve is installed on the fuel manifold, adjacent to the fuel filter.
(5) The fuel flow passage is from the outside diameter of the filter to the inside.
(6) The fuel filter differential pressure sensor is used to find if the primary oil filter element is clogged.
D. Fuel Manifold
(1) The IFPC is installed and sealed on the fuel manifold, adjacent to the fuel flow transmitter and the fuel filter. The IFPC is used to transfer fuel and for connection points for external fuel lines.
(2) Since the fuel manifold moves fuel to and from the IFPC, the IFPC can be removed and replaced without the removal of any fuel lines.
(3) The fuel manifold is installed on the front face of the gearbox on the left side.
E. Fuel/Oil Heat Exchanger
(1) The fuel/oil heat exchanger is used to help the movement of heat from engine oil to engine fuel.
(2) The fuel/oil heat exchanger bypass valve adjusts the amount of oil that flows through the heat exchanger as a function of fuel temperature.
(3) The fuel/oil heat exchanger heats engine fuel to prevent ice collection.
(4) The fuel/oil heat exchanger cools the engine oil for proper engine bearing/seal operation.
(5) The fuel/oil heat exchanger is installed at the 8 o'clock position on the Thermal Management System (TMS).
F. Fuel Nozzles
(1) There are 18 fuel nozzles that are used to atomize fuel for combustion inside the combustor.
(2) There are 12 dual port nozzles that have both a primary and secondary fuel flow path and six single port nozzles that give only a secondary fuel flow path.
(3) The primary fuel flow path is used in the process of the start and the secondary fuel flow path is used in the process of all other power options.
(4) The nozzles are a single vent, moderate fuel pressure drop airflow design, that uses combustor inlet air to atomize the fuel.
(5) Each fuel nozzle inlet connection contains a filter inlet cover and a flow vent.
(6) Each fuel nozzle has its own support cover.