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Miller cycle


  • Only for 4stroke  engines.
  • In Miller cycle inlet valve closes early.
  • NOx reduction , As inlet valve close early when the piston moves down little bit of expansion of inlet air will occur , exhaust temp drops and NOx emission reduces.
  • Normally inlet valve should close around 29 degree after BDC , as the miller cycle introduces , the inlet valve closing is earlier.

Draw back of Miller cycle.

Since the closing of inlet valve is early , the amount of air inside the cylinder is reducing . So further we have to combine it with multistage T\C (To compensate the loss in air )

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