Introduction
• A system for igniting a fuel-air mixture
• Known in the field of IC engines.
• Petrol engines today use an electric spark for ignition
Spark Plug Ignition System
• Commonly referred as petrol engine systems
• Used to run on furls such as petrol, gasoline, autogas, compressed natural gas, hydrogen and nitro-methane.
Fuel inlet
Spark plug
Exhaust gas
Ignition
Working
• High voltage generated
• Voltage difference developed
• Gas expansion takes place
Application
Used in almost all automobiles
Used in generators
Machinery where large amount of fuel is to be burnt.
In Gas Engines
In trimmers and chain saws
Advantages
Copper and iridium spark plugs have got long life
Lower voltage is required.
Increases the engine efficiency.
Installation and maintenance cost is low.
Disadvantages
Damaged/problematic spark plug decreases efficiency.
More amount of CO2 is released.
Less efficient compared to the other.
Homogeneous Charge Compression Ignition System
Mixed fuel and air are compressed to the point of auto-ignition.
This exothermic reaction releases chemical energy.
Advantages
HCCI provides up to a 30-percent fuel savings.
HCCI engines can operate on gasoline, diesel fuel, and most alternative fuels.
Cheaper than presently used engines.
Reduction in the CO2 and NOx content in the exhaust gas.
Lowers combustion temperature.
Dis-advantages
Higher cylinder peak pressures may damage the engine
Auto-ignition is difficult to control
HCCI Engines have a smaller power range
Spark Igniter Vs. HCCI Igniter
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
THERMAL Efficiency CO2 CONTENT
Spark Igniter
HCCI Igniter
Working
All starts with the electrons
Electron releases energy
By having:- Population Inversion- Stimulated Emission- Strategic Planting of Mirrors
A nano-second of pulse is generated.
A d v a n t a g e s
Shorter ignition delay time and shorter combustion time
Fuel-lean ignition possible
Lasers promise less pollution and greater fuel efficiency
Laser use will reduce erosion.
Spark igniter vs. Laser Igniter
0%
10%
20%
30%
40%
50%
60%
Thermal efficiency CO in Exhaust Gas
Spark Igniter
laser igniter
Conclusion
Laser and HCCI Igniters promise less pollution and greater fuel efficiency, but making small, powerful lasers has, until now, proven hard.
Thermal Efficiency of the engines can be increased to a small extent i.e. 10-20%.
REFERANCES
[1] http://en.wikipedia.org/wiki/Ignition_system
[2] http://alternativefuels.about.com/od/glossary/g/sparkignition.htm
[3] http://en.wikipedia.org/wiki/Homogeneous_charge_compression_ignition
[4] http://www.ecogeek.org/content/view/1631/
[5] Applied Thermal Engineering, Unit-4 Ignition Systems
[6] Laser Ignition for Internal Combustion Engines, Nick DeMarcopresentation
[7] Laser Plasma-Initiated Ignition Of Engines, J. Tauer, H. Kofler, K. Iskra, G. Tartar And E. Wintner
[8] Homogeneous Charge Compression Ignition (HCCI) Engine-Need for Society, Prof. Sanjay Harip Government Polytechnic, Nasik, India June, 16th ,2009