Comparison of laser ignition and spark plug by thermodynamic simulation of multi-zone combustion for lean methane-air mixtures in the internal combustion engine

Abstract

Usage of the laser ignition system can potentially solve most of the combustion issues, for instance, low flame velocity, imperfect combustion, and improve the lean-burn limit. In the present study, the ultimate purpose is to investigate the combustion of methane and lean air mixture in an internal combustion engine by laser ignition. Using quasi-dimensional and multi-zone approach, the engine thermal performance parameters for laser ignition and spark plug have been compared. One of the main results obtained is that the use of laser ignition in comparison with the spark plug for methane and air mixture reduces combustion duration at different equivalence ratios. The use of laser ignition improved thermal efficiency by 8.13%, the average pressure by 10%, specific fuel consumption by 27.44%, and the maximum pressure by 37.83% compared to compression spark plug for an equivalence ratio of 0.7. Also, the result of the use of spark plug for the mixture of methane and air with an equivalence ratio of 0.6 was part of the total mixture remaining unburnt, and as the piston approached the BDC position, the unburned mixture remained in the cylinder, while the usage of laser ignition solved this challenge.