Second law analysis of an internal combustion engine for different fuels consisting of NaBH4, ethanol and methanol mixtures

This study was carried out to investigate the effects of NaBH4, which is not used as an internal combustion engine fuel in the literature, on system energy and exergy when used in internal combustion engines. In the study, fuels containing oxygen and hydrogen (MSG12.5, EG12.5, ESG12.5 and MG12.5) and pure gasoline (G100) were tested at different engine speeds and the changes in the energy and exergy analyzes of the system were inves-tigated. In the experimental study, the energy and exergy values of gasoline used as fuel were at the highest values with 33.21 kW and 35.62 kW, respectively, while the energy and exergy efficiencies were 27 % and 25 %, respectively. MG12.5 fuel used in the study showed the best performance among all fuels with 38 % energy efficiency and 35 % exergy efficiency. On the other hand, it was seen that boron added ESG12.5 % fuel was the second best fuel with 35 % energy efficiency and 33 % exergy efficiency. Another fuel, boron added MSG12.5 fuel, performed better than gasoline in terms of both energy and exergy efficiency. In addition, it was determined that more than 50 % of the exergy of the fuel entering the system was lost due to exergy destruction and the exergy destruction of the fuels used in the experiments was determined at least in MG12.5, ESG12.5, EG12.5 and G100, respectively.