Addition of high molecular weight alcohol to diesel-biodiesel fuel mixture effect on engine performance, combustion and emission characteristics

Petroleum-derived fuels are used in internal combustion engines. Despite the ever-increasing number of motor vehicles, the limited lifespan of oil reserves has necessitated the search for alternative fuels. Biodiesel, which is seen as an alternative to diesel fuel and obtained from renewable energy sources, has significant advantages over diesel fuel, as well as generally causing lower engine torque, power and efficiency, while increasing specific fuel consumption. Again, NOx and CO2 emissions increase with the use of biodiesel in diesel engines. Therefore, changes in these values with the addition of alcohol to diesel-biodiesel fuel mixtures have begun to be investigated. Here, short-chain alcohols have low cetane numbers and energy content, so heavy alcohols with longer carbon chains are preferred for diesel engines. As a result of the literature study, butanol (4 carbons), pentanol (5 carbons), hexanol (6 carbons) and octanol (8 carbons), which are alcohols with high molecular weight and high carbon numbers, are added to diesel fuel to improve engine performance, combustion and performance. There are few studies that examine emission characteristics in detail. This study will contribute to the literature. In this master's thesis study, it is aimed that the addition of high molecular weight alcohol to diesel fuel will have positive contributions to engine performance, combustion and emission characteristics. In the experimental study, exhaust emission values ( NOx, CO, CO2, HC and soot) were examined by adding butanol, propentanol, hexanol and octanol as additives to biodiesel-diesel fuel. Then, binary and ternary fuel mixtures were created using biodiesel-diesel-high molecular weight alcohol. As a result of the study, when the exhaust emission behaviors of B10, B20, B30, P10, P20, P30, H10, H20, H30, O10, O20 and O30 test fuels and biodiesel-diesel fuel mixtures added to diesel fuel were evaluated, it was seen that alcohol-containing fuels were more effective than biodiesel-diesel fuel. exhaust gas temperature and NOx emissions increased; It was determined that CO, HC and soot emissions decreased.