Describe air fuel- ratio requirements for diesel engines at no load to full load.

Describe air fuel- ratio requirements for diesel engines at no load to full load.
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Irrespective of load at any given speed, an approximately constant supply of air enters the cylinder. With change in load, the quantity of fuel injected is changed varying the air fuel ratio. The overall air fuel ratio thus varies from about 18:1 at full load to about 80:1 at no load. The diesel engine always designed to operate with an excess air of 15 to 40% depending upon the application
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