Análise dos parâmetros de desempenho de um motor de ignição por centelha operando com gasolina ou etanol com adição de hidrogênio

Abstract

This work presents a computational study about the effects of the application of hydrogen as complementary fuel to gasoline and ethanol in a spark ignition engine, verifying the modifications of the engine performance parameters. In the research a numerical study was carried out, adopting a quasi-dimensional model for a combustion, simulating the engine operation for equivalence ratios of the mixture air/fuel in λ=1,00; 1,07 e 1,14. Using experimental data from the literature, the fraction of hydrogen used, which was produced in electrolysis process together with oxygen gas in the proportion of 2:1, represented 1.27% of the total volume of air admitted to engine operating at 840 rpm and 0.38% for rotation of 1400 rpm. Using the AVL Boost® software, the effects of the addition of hydrogen were analyzed, where a reduction in the duration of combustion and higher rates of heat release was observed, increasing the thermal efficiency of the engine, as well as it was verified increase peak pressure in the cylinder and the IMEP. It was concluded that the higher speed of the combustion process acquired by the addition of hydrogen allows spark ignition engines to operate with air/fuel blends impoverished, returning in reduction of specific fuel consumption.