• Energy Research
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Abstract Diesel engines are used widely as they have lower fuel consumption and higher thermal efficiency in transportation sector. However, the emitted high NO x , CO and soot emissions have led researchers to search different alternative fuels. At this point, diesel fuels emulsions help to reduce exhaust emissions. In this study, the effects of diesel fuel emulsions containing 5% (E5) and 10% (E10) water on engine performance an exhaust emissions has been investigated. Mono ethylene glycol was used as an auxiliary emulsifier in the preparation of the emulsion. Use of the mono ethylene glycol reduced the subsidence rate of the E5 and E10 about 34.5% and 47.1% respectively. The experiments were conducted at full load condition and at 2500, 3250 and 4000 rpm engine speeds. Engine torque and power increased according to diesel fuel between 2400 and 3600 engine speed range when emulsified fuels were used. But significant reductions were observed after that engine speed range. It was observed that the nitrogenoxide (NO x ) emission reduced 5.42% and 11.01% with using E5 and E10 fuel respectively according to diesel fuel at 2500 rpm. Also the soot emissions reduced 12.39% and 22.97% with using E5 and E10.

Abstract In this study, chicken fat biodiesel with synthetic Mg additive was studied in a single-cylinder, direct injection (DI) diesel engine and its effects on engine performance and exhaust emissions were studied. A two-step catalytic process was chosen for the synthesis of the biodiesel. Methanol, sulphuric acid and sodium hydroxide catalyst were used in the reaction. To determine their effects on viscosity and flash point of the biodiesel, reaction temperature, methanol ratio, type and amount of catalyst were varied as independent parameters. Organic based synthetic magnesium additive was doped into the biodiesel blend by 12 μmol Mg. Engine tests were run with diesel fuel (EN 590) and a blend of 10% chicken fat biodiesel and diesel fuel (B10) at full load operating conditions and different engine speeds from 1800 to 3000 rpm. The results showed that, the engine torque was not changed significantly with the addition of 10% chicken fat biodiesel, while the specific fuel consumption increased by 5.2% due to the lower heating value of biodiesel. In-cylinder peak pressure slightly rose and the start of combustion was earlier. CO and smoke emissions decreased by 13% and 9% respectively, but NOx emission increased by 5%.

The main disadvantages of HCCI engines are the knocking tendency at high engine loads, the challenge of the start of the combustion, control of the combustion phase, and the narrow operating range. In this study, we aimed to control the combustion processes in HCCI engines and to expand their working range by improving the fuel properties of fusel oil by the addition of diethyl ether. Thus, the variations in the in-cylinder pressure, rate of heat release, indicated mean effective pressure, start of combustion, combustion duration, CA50, indicated thermal efficiency, mean pressure rise rate, hydrocarbon and carbon monoxide emissions were investigated. It was observed that the in-cylinder pressure and rate of heat release were taken into advance and the test engine could be operated for a wider range by increasing the diethyl ether ratio in the blend. The indicated mean effective pressure increased by 67.5% with DEE40 fuel compared to the DEE80. Under the same operating conditions, HC and CO emissions decreased by 41.6% and 56.2%, in use of DEE40. Furthermore, the highest indicated thermal efficiency was obtained as 42.5% with DEE60 fuel. Maximum hydrocarbon and carbon monoxide emissions were observed with DEE80 fuel as 0.532% and 549 ppm, respectively.