02-04-2011, 04:37 PM
Presented by:
Joseph Simon Clark
[attachment=11607]
Homogeneous Charge Compression Ignition (HCCI) Engines
What is an HCCI Engine?
• HCCI is a form of internal combustion in which the fuel and air are compressed to the point of auto ignition.
• That means no spark is required to ignite the fuel/air mixture
• Creates the same amount of power as a traditional engine, but uses less fuel.
How Does It Work?
• A given concentration of fuel and air will spontaneously ignite when it reaches its auto-ignition temperature.
• The concentration/temperature can be controlled several ways:
– High compression ratio
– Preheating of induction gases
– Forced induction
– Retaining or reintroducing exhaust gases
Advantages
• Can achieve up to 15% fuel savings
• Lower peak temperature leads to cleaner combustion/lower emissions
• Can use gasoline, diesel, or most alternative fuels
Disadvantages
• Higher cylinder peak pressures may damage the engine
• Auto-ignition is difficult to control
• HCCI Engines have a smaller power range
The Future of HCCI
• The future of HCCI looks promising
• Major companies such as GM, Mercedes-Benz, Honda, and Volkswagen have invested in HCCI research.
• Preliminary prototype figures show that HCCI cars can achieve in the area of 43 mpg
Joseph Simon Clark
[attachment=11607]
Homogeneous Charge Compression Ignition (HCCI) Engines
What is an HCCI Engine?
• HCCI is a form of internal combustion in which the fuel and air are compressed to the point of auto ignition.
• That means no spark is required to ignite the fuel/air mixture
• Creates the same amount of power as a traditional engine, but uses less fuel.
How Does It Work?
• A given concentration of fuel and air will spontaneously ignite when it reaches its auto-ignition temperature.
• The concentration/temperature can be controlled several ways:
– High compression ratio
– Preheating of induction gases
– Forced induction
– Retaining or reintroducing exhaust gases
Advantages
• Can achieve up to 15% fuel savings
• Lower peak temperature leads to cleaner combustion/lower emissions
• Can use gasoline, diesel, or most alternative fuels
Disadvantages
• Higher cylinder peak pressures may damage the engine
• Auto-ignition is difficult to control
• HCCI Engines have a smaller power range
The Future of HCCI
• The future of HCCI looks promising
• Major companies such as GM, Mercedes-Benz, Honda, and Volkswagen have invested in HCCI research.
• Preliminary prototype figures show that HCCI cars can achieve in the area of 43 mpg
