Enhancement of SI engines performance operating with gasoline fuel using high octane additives from waste materials

Abstract

Fuel property is an important indicator for the fuel suitability to utilize in an internal combustion engine. It can influence the combustion efficiency and fuel consumption directly. In this study, investigation of the effect of fusel oil additive with commercial gasoline at different ratios on the properties of fuel blend and SI engine performance based on gasoline fuel as a threshold for comparison. The engine performance test was conducted at increasing speed and constant half load. Study results reveal that fusel oil has a higher density while the blended fuel samples have a density value closed to that of petroleum with a similar trend of change of viscosity. The higher measured octane number indicated for fusel oil with a value of 106 and the lower octane number for petroleum fuel is 86, which is less than that of fusel oil by about 19%. On the other hand, the higher measured energy content indicated with petroleum fuel at a value of 45.5 MJ/kg while the lower energy content for fusel oil of 29.5 MJ/kg which is lower than that of petroleum fuel by about 33%. Moreover, it can be seen that the energy content of blended fuel decreased with increasing fusel oil additive ratio to 5% and 10% respectively. Engine test shows an increase in brake power at low speed of 1200 rpm by 9% and 15% with PF5 and PF10 respectively compared to pure petroleum, which further enhanced with increasing engine speed. Slight variation in BSFC observed with the increasing additive ratio at medium engine speed with less variation at low and high engine speed at lower BSFC for petroleum fuel over the whole engine speed. Finally, significant variation in engine BTE observed with increasing additive ratio in the blend with gasoline, which indicates significant improvement in the fuel combustion efficiency.