Fuel injection and Parts. uses in engine

mechanical Engineering:- Engine part used for Fuel Injecting purposes.
types of Fuel injection
Tpes of nozzels

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2. THERMODYNAMICS LAB PRESENTATION PRESENTED BY :- MOIN ZEB & TAUSEEF KHAN CLASS NO:- 118 & 125 DEPARTMENT OF MECHANICAL ENGINEERING 2

3. Mechanical system  inject atomized fuel  directly or indirectly  replacement of carburetor -:FUEL INJECTOR:- 3

4. Background Types Of Fuel Injectors Mechanical Fuel Injector Electronic Fuel Injector Types Of Injections Direct injection Indirect Injection Parts Of Fuel Injector Types of Nozzle It’s Working Advantages and Disadvantages of Fuel Injection Conclusion -:Outline of Presentation:- 4

5. All internal combustion engines require a device to mix the fuel and air before being ignited by the spark plug Necessary for all engines -:Background:- 5

6. Mechanical Fuel Injector :- pressure of the fluid overcome the elastic pressure of spring and fuel in injected. Electrical Fuel Injector:- Several sensor are used that are controlled by ECU (electronic control unit). 6 -:Types OF Fuel Injectors:-

7. Direct Injection System In which the air and fuel mixed inside the cylinder Diesel enignes are mostly direct injection Air from the intake manifold and fuel from the fuel injector come to combine inside the cylinder. 7 -:Types of Injection systems:-

8. Indirect Injection System:- petrol being injected into the inlet manifold or inlet port rather than directly into the combustion chambers. This ensures that the fuel is well mixed with the air before it enters the chamber. petrol engine cars is always indirect, 8

9. Nozzle Needle nozzle Valve control plunger Solenoid valve Inlet hole Outlet hole Valve control chamber overflow 9 -:Parts Of Fuel Injector:-

10. 10 EXPLODED VIEW DIAGRAM

11. open View Diagram 11

12. Alloy steel Nozzle needle an body Pressure spring and spindle hold the needle The injector pump delivers fuel to the injector… fuel passes through the drilling in the nozzle body…to the chamber where the nozzle valve seeps into the nozzle assembly as the fuel pressure in the injector gallery rises…it acts on the tapered shoulder of the needle valve… increasing the pressure until it overcome the ELASTIC force coming from the spring and lifts the needle valve from its seat.. The highly pressurized fuel enters the engine with high velocity in an atomized spray. As soon as the delivery from the pump stops.. Pressure under the needle tapered shoulder drops.. Spring force pushes the needle valve to its seat. Cutting off fuel supply to the engine… Some of the fuel allowed to leak between the nozzle needle and the body to cool and lubricate the injector. This fuel is collected by the leak of line and returned to the fuel tank for later use 12 WORKING

13. Pintle nozzle: Stem of nozzle valve is extended to form a pin or Pintle which protrudes through the mouth of nozzle. Provides a spray operating at low pressure, 8-10 MPa . Spray cone angle is generally 60 degree. It avoids weak injection and dribbling. 13

14. Pintaux nozzle: Similar to Pintle nozzle but a auxiliary hole is drilled in the nozzle body. Hence it helps in injection of small amount of fuel through it slightly before the main injection. The needle valve does not open fully at low speed and most of fuel is injected through the auxiliary hole.   Provides better cold starting of engine. 14

15. Single hole: At the center of nozzle body there is single hole which is closed by the nozzle valve. Order of hole is generally order of 0.2mm Injection pressure is in the order of 8- 10MPa and cone angle is 15 -20 degree. Major disadvantage is that it tend to dribble Small cone angle facilitates good mixing unless higher velocities are used. 15

16. Multi hole: Contains number of holes drilled in the tip of nozzle. Holes may vary from 4-18 in numbers and in size 35 to 200 µm. Injection pressure is of order of 18-20 MPa and cone angle is greater that 20 degree. Ability to distribute the fuel properly even with lower air motion available in open combustion chambers. 16

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18. Engine performance viz. power output, economy ( equivalence ratio is maintained ) Accurate metering ( errors may cause drastic variation from the desired output .) Proper atomization of fuel equal quantity of metered fuel (in case of multi cylinder engines) 18 Advantages of FUEL INJECTOR

19. Injection is superior to carburetion Indirect injection is easier and therefore more common to implement Direct injection is more efficient Increasing the pressure differential across a fuel injector is the most effective way to improve performance Increasing the nozzle area is the easiest 19 CONCLUSION