The effect of the blends of isopropanol-butanolethanol (ibe) with diesel and biodiesel fuels on combustıon and emission characteristics in a diesel engine

In present thesis study, the effect of the blends of isopropanol-butanol-ethanol (IBE) with petroleum based diesel and biodiesel fuels on combustion and emission characteristics is investigated when they are used in a single-cylinder, four-stroke and direct injection diesel engine as fuel. With this purpose, IBE10, IBE20 and IBE30 blended fuels that obtained by the mixture of IBE at ratios of 10%, 20% and 30% with petroleum diesel fuel were tested under constant engine speed of 2400 rpm and different load cases which corresponds to 20%, 40% and 60% of max. Torque, 300 bar of injection pressure and 190CA of injection timing, and the change in combustion and exhaust emissions was investigated in comparison with the use of diesel fuel. Experimental results have shown that the addition of IBE to diesel fuel at low load conditions delayed the combustion while an increase in load reduces this delaying. Besides, using IBE led to an increase in cylinder gas pressure values except for low load case. Despite heat release has shown an increase for all loads, this increase is not proportional with the amount of IBE in fuel. CO emissions have not shown an important change with the change in load and IBE rate in fuel, however despite unburned HCs have increased with the increase of IBE ratio at low load, decreased at 60%load. The change in NOx emissions is not proportional with the blending ratio while the use of IBE smoke opacity reduced considerably. While the use of IBE10 at 20% load caused the increase in NOx, it decreased when IBE20 and IBE30 were used. A similar case is observed at 60% load condition. For 40% load, NOx has increased with the increase of IBE in fuel. In this case, to improve the present study IBE30 was tested again at 60% load however at different injection timings including 150CA, 170CA, 210CA and 230CA. When IT was set as 150CA and 170CA, this caused to an decrease in the values of pressure and heat release as well as NOx however an opposite trend was observed with 210CA and 230CA that these values increased more than previous. The tests were repeated by the mixtures of IBE30 at the rates of 80% and 60% by volume with biodiesel under previous operating conditions. Adding biodiesel increased pressure and heat release, moreover unburned HC and NOx emissions reduced.