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WORKING PRINCIPLE OF FUEL INJECTOR

FUEL INJECTOR


FUEL INJECTOR
It is valve through which fuel is sprayed or injected in the combustion space of internal combustion engine. Therefore it is also called fuel valve . It has given with below three basic purposes.
  1. Atomization - The process of breaking of fuel into small tiny particles during the time of injection. The size of fuel particles is about 10 mm in diameter.
  2. Penetration - It  is the distance travelled by tiny fuel particles in the combustion chamber before combustion.
  3. Turbulence- Swirll or rotating  movement of fuel along with charge air in  the combustion chamber . It improves the mixing of fuel and air.

WORKING PRINCIPLE OF FUEL INJECTOR 

When fuel pump plunger rises up in the barrel , fuel come into the chamber of fuel injector and pressure starts build in the chamber underside of the needle valve and when the fuel overcomes the spring force , needle valve is opened and fuel passes through  the small clearance between the valve and valve seat where eddies friction is formed between the  layer of fuel . Now at this time fuel pressure is acting  on the complete  seating area of the needle  valve  causes valve to lift more and  open. And finally this fuel comes out from the nozzle as a atomised spray .

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