Combustion and Emission Characteristics of Gasoline Engine Blended Combustion Syngas

Abstract

It is an effective way to introduce syngas fuel into gasoline engine for blending combustion to improve combustion and reduce emissions. In this paper, the combustion and emission characteristics of the direct injection engine under the condition of mixed combustion of syngas were analyzed by a numerical simulation method. The engine ran at 2000 rpm, and the mass fraction of syngas was from 0 to 20%. The results showed that with the increase in the mass ratio of syngas in the dual fuel, the average pressure and temperature in the cylinder increased first and then decreased. The maximum in-cylinder pressure and in-cylinder temperature increased by 27.5 and 2.97%, respectively. The instantaneous heat release rate also showed a law of first increasing and then decreasing, in which the peak value of the instantaneous heat release rate increased by 32.1% at the highest. In addition, with the increase in the ratio of syngas, the emission of nitrogen oxides in the cylinder gradually decreased, with a maximum reduction of 27.4%. The unburned hydrocarbons first decreased and then increased, with a maximum reduction of 7.6%. Meanwhile, the emission of carbon dioxide was negatively correlated with the ratio of syngas in the dual fuel. With the increase in hydrogen ratio in syngas, the carbon monoxide was gradually reduced, with a maximum reduction of 65%. The carbon dioxide increased first and then decreased, with a maximum addition of 4.8%. The ratio of hydrogen and carbon monoxide in syngas had little effect on the emission of unburned hydrocarbons.

Analysis of Various Factors’ Influence and Optimization of Low-Temperature Combustion Technology

“…In this case, the hot spots can occur on the internal surface of the combustion chamber, and this fact excludes utilization possibility of low-reactive fuel with high octane number. The described complication requires application of additional cooling focused on such points, which can be overheated during the combustion process, e.g., the fuel injectors …”

“…The described complication requires application of additional cooling focused on such points, which can be overheated during the combustion process, e.g., the fuel injectors. 20 …”