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The main aim of this work is to characterize the combustion phenomena and particulate matter in nano-size from the reactivity controlled compression ignition (RCCI) engine using neat hydrous ethanol as a low reactivity fuel. A four-cylinder diesel engine fueled with diesel (the volumetric blend of 95% petroleum diesel and 5% palm-based biodiesel) was operated on low and medium loads at 2,500 rpm without main diesel fuel injection modification and exhaust gas recirculation. Ethanol was injected at 1 bar pressure into the intake manifold while the w/w ratios of ethanol:diesel were varied between 0 and 0.77. An engine indicating system composed of an in-cylinder pressure transducer and a shaft encoder was used to investigate combustion characteristics using the first law of thermodynamics. A Scanning Mobility Particle Sizer and an Optical Particle Sizer were used to determine the particle number concentration and distribution over nano-size range.

The increase of air pollution and global warming is a threat for human life. Besides, the price of petroleum is increasing rapidly and the resources are diminishing. This obliged scientists and engineers to look for alternative sources of energy, which are cleaner and more sustainable. Biodiesel, defined as mono-alkyls of esters from vegetable oils and animals fat, is a cleaner renewable fuel and has been considered as the best alternative for petroleum based diesel fuel hence it can be used in any compression ignition engines without any significant modification. The main advantages of using biodiesel are its renewability and better quality of exhaust gas emissions due to their higher content of oxygen. The produce less soot and hence the feed stuck is plant it will regenerate the CO2 by the photosynthesis which ensures the renewability and reduces global warming.

Nowadays, the diesel engine models are developed from a unit pump to a common-rail injector. With palm methyl ester (commonly known as biodiesel) with higher viscosity and density than conventional diesel being used as alternative fuel for diesel, palm methyl ester may affect the injection characteristics. Injection pressure is one of the important parameters of common rail injector. Because of its effects on the pressure between command port and control volume, which activates a needle lift during injection process. This paper presents injection characteristics of solenoid injector experimented in a Zeuch’s chamber with a focus on injection pressure frequency, injection pressure amplitude, injection pressure stable duration. Commercial diesel (with mandate of 5% biodiesel blend or B5) and palm methyl ester (B100) were used as the test fuels at various injection pressures (40, 80, 120 and 160 MPa).

Formerly, the Hydro-treated Vegetable Oil (HVO) blended fuels has been studied by running the New European Driving Cycle (NEDC) and found that the higher HVO blended fuel can suppress NOX, lowering the particulate matter (PM) while improving the vehicle fuel economy. The result also shown that the 20% HVO + 5%FAME blended with diesel fuel has been proven to compatible with the advance diesel engine technology via the severe engine durability tests and fuel injection system tests. Therefore, the effects of two paraffinic diesel fuels, which are Gas-to-Liquid (GTL) and Hydro-treated Vegetable Oil (HVO), on a common-rail DI diesel engine have been mainly focused in this work. The main objective of this work was to study the relationships between fuel properties and theirs combustion characteristics by analyzing cylinder pressure data and exhaust emissions intensively.

The purpose of this study is to investigate the startability characteristics of a single cylinder direct injection compression ignition engine fueled with ethanol and blended with ignition improvers. The engine is modified to increase the compression ratio from 18:1 to 23:1 and 28:1. In this study, glycerol ethoxylate and palm oil methyl ester (POME) are considered as the ignition improvers blended with ethanol in various concentrations. Engine speed is used as the key parameter to explain the startability characteristics and categorize them into four types. Type A has excellent engine startability similar to diesel. Type B has good engine startability. Type C has fair engine startability. Engine startability for Type D is unsuccessful. The results show that increasing the concentration of the ignition improver enhances engine startability and reduces the number of misfiring cycles due to improvements in combustion.

The effects of high quality biodiesel, namely, partially Hydrogenated Fatty Acid Methyl Ester or H-FAME, on 50,000km on-road durability test of unmodified common-rail vehicle have been investigated. Thailand popular brand new common-rail light duty vehicle, Isuzu D-Max Spacecab, equipped with 4JK1-STD engine (DOHC 4-cylinder 2.5L, M/T 4×2, Euro III emission) was chosen to undergo on-road test composed of well-mixed types of mountain, suburb and urban road conditions over the entire 50,000km. Jatropha-derived high quality biodiesel, H-FAME, conforming to WWFC (worldwide fuel charter) specification, was blended with normal diesel (Euro IV) at 10% (v/v) as tested fuel. Engine performance (torque and power), emission (CO, NOx, HC+NOx and PM), fuel consumption and dynamic response (0-100km acceleration time and maximum velocity) were analyzed at initial, middle and final distance; whereas, used lube oil analysis was conducted every 10,000km.