Fuel

Question 1

Purpose of a fuel system

Answer 1

To supply a precise amount of clean vapor free fuel to the combustion section of the engine,
At a pressure and temperature suitable for efficient atomisation/vaporization

Question 2

Components in fuel sys [8]

Answer 2

Lp fuel pump
Fuel cooled, oil cooler
Fuel heater (bleed air)
Lp filter
Hp pump
Hp filter
FCU
P&D valve

Question 3

2 types Fuel pump

Answer 3

Constant displacement

Variable displacement

Question 4

FCU types [3]

Answer 4

Hydromechanical
Hydropneumatic
Electronic

Question 5

Hydromechanical does..

Answer 5

Computing and fuel metering

Question 6

FCU parameters [4]

Answer 6

Power lever position
Engine speed
Compressor inlet temp and pressure
Burner / discharge temp and pressure

Question 7

Outline P&D valve

Answer 7

Pressurises fuel to correct pressure

And dumps fuel on engine shutdown to prevent (hotstarts)

Question 8

Fuel nozzles types

Answer 8

Atomization
- simplex
- duplex
Vaporization

Question 9

Outline simplex and duplex

Answer 9

Simplex is primary nozzle for start up (wider spray)

Duplex two nozzles and has a narrower spray