We replace conventional spark plug by laser ignition. Since spark plug are less efficient, we have chosen a laser ignition system. Laser has many advantages over spark. It wil help to increase efficiency of the engine.
Why Laser Ignition....
Regulations on NOx emissions are pushing us toward leaner air/fuel ratios (higher ratio of air to fuel).
These leaner air/fuel ratios are harder to ignite and require higher ignition energies. Spark plugs can ignite leaner fuel mixtures, but only by increasing spark energy. Unfortunately, these high voltages erode spark plug electrodes so fast, the solution is not economical. By contrast, lasers, which ignite the air-fuel mixture with concentrated optical energy, have no electrodes and are not affected.
Natural gas is more difficult to ignite than gasoline dueto the strong carbon to hydrogen bond energy.
Lasers are monochromatic, so it will be much easier to ignite natural gases and direct the laser beam to an optimal ignition location.
Because of the requirement for an increase in ignition energy, spark plug life will decrease for natural gas engines.
Laser spark plug ignition system will require less power than traditional spark plugs, therefore outlasting spark plugs.
Ignition sites for spark plugs are at a fixed location at the top of the combustion chamber that only allows for ignition of the air/fuel mixture closest to them.
Lasers can be focused and split into multiple beams to give multiple ignition points, which means it can give a far better chance of ignition.
Future reasearch needs and other shortcomings....
Concept proven, but no commercial system yet available.
Stability of optical window
Beam Delivery/Laser induced optical damage
Multiple pulse ignition
Multiple point ignition
Single Point Ignition:
Timing optimization (phasing) vs Thermal Efficiency
Higher flame speed may provide additional knock margin as well as a higher burn rate.
May provide improved ignition, leaner combustion, and lower emissions.
May provide a way to circumvent beam delivery issue.