5.11 Fuel cooler
Extremely high injection pressure increases the temperature of the uncombusted, depressurized fuel when it
is returned to the tank. This may lead to high fuel return temperature and, in consequence, to an engine
shutdown. Moreover, excessive temperatures could exceed the material-dependent temperature limits of the
day tank and the injection system.
A fuel cooler reduces the fuel temperature in the fuel return line and day tank.
The illustration below shows a front and side view of the fuel cooler.
1 Fuel cooler housing
2 Connection for fuel outlet
3 Electric motor
4 Heat exchanger
5 Connection for fuel inlet
6 Axial fan with fan guard
a Fuel
b Air
Function
The fuel cooler is installed in the fuel return line between the engine and the fuel tank.
Uncombusted, heated fuel (a) flows through the fuel inlet (5) into the heat exchanger (4), which is made of
heat-resistant aluminum. Air (b) drawn through an aluminum radiator block by an axial fan (6) dissipates heat
from the fuel. After passing through the heat exchanger (4) comprising a row of pipes, the air-cooled fuel is
returned to the fuel tank via the fuel outlet (2).
The axial fan (6) is driven by an electric motor (3). The air (b) is drawn into the housing of the fuel cooler (1)
by the rotating blades of the fan. Heated air exits the fuel cooler after cooling the fuel in the heat exchanger.
Benefits
• Fuel cooling prevents engine shutdowns due to excessive fuel temperature
• Improved plant safety by reducing the fuel temperature in the day tank
• Less need for additional engine coolant which reduces costs
62 | Functional Description | MS15060/01E 2018-12
TIM-ID: 0000082959 - 001
