Aspects of experimental investigations of laser plug ignition use at spark ignition engine

Nowadays, the necessity of pollutant emissions reduction brings to the fore new technologies developed for a better control of the combustion process. Ignition is the process of starting radical reactions until a selfsustaining flame has developed and strongly affects the formation of pollutants. Among the new technologies used for ignition and combustion control, the Laser Plug Ignition system is defined as an innovative technology which overcomes several limitations of conventional spark ignition. Laser ignition technology presents many advantages for engine operating control, engine performance improvement and pollutant emissions reduction. The objective of the paper is the experimental research of the laser ignition used in the spark ignition engine. The laser plug ignition system was mounted on an experimental spark ignition engine and tested at the regime of 90% load and 2800 rpm and dosage, λ = 1. The experimental results present the influence of laser ignition on different engine parameters compared to electric spark ignition. The influence on in-cylinder pressure, heat release rate, engine efficiency and pollutant emissions level is analyzed. Compared to a conventional spark plug, a laser ignition system assures efficient engine operation at lean dosages.