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Why 3 fuel injectors are used instead of single injectors

  • Modern crosshead engine fitted with a centrally mounter exhaust valve utilize uniflow scavenging
  • Because of this , 3 injectors are placed circumferentially around the cylinder head.
  • The atmosing holes , which are of different design to those of centrally placed injectors are designed to inject the fuel into the air swirl without contacting the liner surface.
  • A single injector could not be used because because it would result in poor air/fuel mixing with poor combustion and localized high temperature, although some ebgine utilizes 2 injectors per cylinder.
  • Due to tangential design of the scavenge ports ,chatge air rotates around the cylinder acts in swirl action which promotes better mixing of fuel from 3 injectors and the air.
  • This overall result in uniform temp distribution , more efficient combustion and lower exhaust temperature

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