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1.5L REVOTORQ ENGINE
90
H. FUEL SYSTEM
Introduction
1.5 L engine incorporates a new technology that
injects diesel into the cylinders, through electronically
controlled fuel injectors. The fuel is pre pressurized
before being injected into the cylinder.
Description
A tube or common rail having fuel at constant high
pressure connects all the injectors. The high
pressure in the common rail ensures that when fuel
is injected, the fuel breaks into fine particles and
mixes evenly with air, thereby leaving little unburned
fuel, hence increasing fuel efficiency and reducing
pollution. The common rail technology also reduces
noise.
1.5 CRAIL System
The 1.5 CRAIL engine from TATA uses DELPHI high
pressure pump to supply diesel to cylinders, through
a common rail and electronically-controlled injectors.
The high pressure in the common rail ensures
that when fuel is injected, the fuel breaks up into
small particles and mixes evenly with the air,
thereby leaving little un-burnt fuel, thus reducing
pollution. The common rail principle has been
used to cut out the noise factor which is
associated with diesel engines.
The brain of 1.5 L engine is Electronic Control
Unit (ECU), which aids engine functioning at its
optimal capacity. The ECU continuously receives
signal from sensors installed at various locations
in the vehicle.
The ECU also receives continuous input from rail
pressure sensor, which monitors the fuel pressure
depending on engine speed and load. Depending
on the position of throttle pedal, the ECU sends
signal to high pressure pump through Inlet
Metering Valve (IMV), to send the required
quantity of fuel to common rail, thus improving the
fuel consumption. The fuel gets distributed
through the common rail to each electronically
controlled injector. The ECU then sends signal to
the injectors, on the quantity of fuel to be injected
to produce the required power.
The fuel is injected into the combustion chamber
at specified time and pressure, thereby increasing
the power output and efficiency. The entire
process takes less than a second.
Finally, to control the exhaust emission, the
Exhaust Gas Re-circulation (EGR) valve returns
unburnt fuel to the combustion chamber for
further combustion, thereby reducing the release
nitrogen oxide and other particulate matter to
atmosphere.
Features of 1.5 CRAIL system
1.5 CRAIL is powered by 1.5 CRAIL engine uses
advanced Delphi 1600 bar electronic common rail
injection system.
The ECU constantly monitors functioning of
various sensors and actuators and detects the
faults generated in the system and indicates the
status of fault through the check engine lamp.
1.5 CRAIL engine automatically adjusts to suit
External environment conditions.
Cylinder balancing: The engine speed is well
balanced by reducing cyclic variations in the
engine as all the parameter of injectors/injection
system, are controlled by ECU.
Anti-Oscillation Strategy (AOS): The AOS
reduces jerks during sudden accelerations. The
engine speed, vehicle speed and gear change is
continuously monitored and adjustments are
made to enhance driving pleasure.
Advantages of 1.5 CRAIL Technology
Electronically controlled fuel injection system.
High pressure injection (1600 bar) for better
emission and pilot injection to reduce noise,
vibration and harshness (NVH).
Highest power and torque.
Excellent drivability.
Improved grade ability / restart ability.
Excellent cruising ability, lower fuel
consumption
Improved noise characteristics.
Smoother running and enhanced driving
pleasure.