Fuel Injection systems

1.  Unit – II Compression ignition engines
 Prepared by
 Mr. P. SELVAN M.E., (Ph.D)
 Assistant Professor
 Department of Mechanical Engineering
 Kamaraj College of Engineering and Technology
 Virudhunagar

2. COMMON RAIL DIRECT INJECTION
ENGINE

3. PROBLEM IDENTIFICATION
 Conventional CI and SI engines use gasoline
and diesel as a fuel.
 The problem with diesel fuel is that diesel
particles are larger and heavier than gasoline.
So it is more difficult to atomize.
 Unburned particles, causing more pollution,
lower efficiency and less power.
 In order to overcome these problems high
pressure fuel injection system developed.
Engines that use technology is called CRDI.

4. CRDI
 Common rail injection system mostly
suitable for diesel engine. This system is
improve the atomization process by means
of very high pressure( upto 1800 bar).
 CRDI system uses appropriate sensors to
provide real time combustion for each
cylinder by controlling of ECU controller.

6. CRDI ARRANGEMENT
 The common rail which is placed upstream
of the cylinder act as a accumulator. It
distributes the fuel to the injectors at a
constant pressure of up to 1800 bar.
 In ECU system high speed solenoid valves
used to electronically controlled engine
management system. It control the injection
timing and the amount of fuel injected for
each cylinder by function of cylinders
actual need.

7. SPRAY PATTERN

8. MERITS
 Better fuel atomization.
 Reduced explosiveness and vibration.
 Lower exhaust emissions.
 Possible of 30% fuel economy in each
cylinder.

9. DEMERITS
 Higher capital cost.
 Difficult maintenance ensures costlier.

10. ELECRONICALLY CONTROLLED DIESEL
INJECTION SYSTEM

11. ELECTRONIC-DIESEL CONTROL

12. STAGES OF COMBUSTION IN A CI ENGINE

13. COMBUSTION PROCESS IN A CI ENGINE

14. OPEN COMBUSTION CHAMBER

15. THANK YOU