الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The invention of internal combustion engine and subsequent developments in engine technology led to widespread exploitation of the petroleum reserves, which were being depleted at a rapid rate. Moreover, the combustion of these fuels has polluted environment. Many researchers have concluded that biodiesel holds promise as an alternative fuel for diesel engines. Biodiesel is oxygenated, biodegradable, non-toxic, and environmentally friendly. It consists of the alkyl monoesters of fatty acids from triacylglycerols, and can be produced from vegetable oils, animal fats, and waste restaurant grease [1-2].
In this study, the performance parameters and exhaust emissions of a single cylinder, variable compression, four-stroke diesel engine using diesel fuel and biodiesel, have been investigated for the cases of both naturally aspirated (NA) and supercharged (SU) conditions. The percentages ofbiodiesel were tested are: 10% (B I 0),20% (B20), and 50% (B50) In addition, pure diesel fuel (BO) was tested to establish the 0% biodiesel point. The tests were performed at compression ratios of 14, 16 and 18 and at engine speeds ranging from 1000 to 2000 rpm with intervals of 250 rpm at fully opened throttle conditions for each speed and the experimental results were compared with each other. The engine was first fuelled with diesel fuel to determine the baseline parameters of the engine at NA condition and then, it was fuelled with biodiesel. After tests were completed with diesel and biodiesel fuels for NA engine operation, a supercharger with a boost pressure of about I Ommhg and 20 mmhg was used. The results showed that brake specific fuel consumption (BSFC) and nitrogen oxides (NOx) emissions increased while brake thermal efficiency, engine torque (BTE), carbon monoxide (CO) and hydrocarbon (HC) decreased with the increase in the amount of biodiesel in the fuel mixture. The best results for BSFC and BTE were observed at increased the compression ratio (CR). This study reveals also that the use of biodiesel improves the performance parameters of the supercharged engine compared to diesel fuel.