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[자동차공학] HCCI에 대한 자료입니다.
목차
What is HCCI?
HCCI process
Advantage of HCCI
Challenges of HCCI
Future of HCCI
본문내용
HCCI is Homogeneous Charge Compression Ignition
HCCI engine concept combines aspects of SI and Diesel engines by compression igniting a pre-mixture of fuel and air.
No flame propagation or mixing controlled combustion – global auto-ignition of the charge .
Can use uniformly ultra-lean mixtures, giving low peak combustion temperatures, near zero NOx emissions.
Auto-ignition is said to occur simultaneously at many locations, called hot spots, throughout the cylinder.
The most common means used to facilitate auto-ignition (for a high RON fuel) are:
Increasing the compression ratio.
Using intake air heating.
Using internal EGR by trapping combustion products by some method that can alter valve timing and/or lift (e.g. VVT, valvetronic, EVC).
Running the engine on fuel mixtures with different reactivities and controlling the fraction of each fuel.