Performance analysis (WHP and torque) on SI engine fueled with low-grade bioethanol and oxygenated fuel additive

Utilization of renewable energy in Indonesia is still relatively low compared to the non-renewable energy source of petroleum, coal, and natural gas. The limited amount of the non-renewable energy encourages the development of alternative fuels. Currently, low-grade bioethanol is one of the alternative fuel being developed. Bioethanol has a higher octane number compared to gasoline. Mixing of bioethanol requires a certain comparison, the mixing is intended to increase the octane number of a fuel mixture. The use of low-grade bioethanol (C2H5OH) as a substitute or mixture of fuels has an impact on engine performance. To get a more optimal effect on the fuel mixture, oxygenated cycloheptanol as an additive can be added to the fuel. This study examined the effect of fuel mixture with the addition of oxygenated cycloheptanol to single cylinder SI engine, 150 cc premix type at 100% throttle position. The tests was carried out on E5, E10, E15 and the addition of 0.5% oxygenated cycloheptanol at each fuel mixture with engine speed variation above 4000 rpm. Performance test will be performed with connecting the machine to a dynamometer. This study aims to obtain efficient performance on the engine with the addition of additives, there is an average increase of 9% in horsepower and 6% in torque.