Application and comparison of soy based biodiesel fuel to ultra low sulfur diesel fuel in a HPCR diesel engine - Part II: combustion and emissions

Biofuels have the potential to diversify transportation energy sources and reduce dependence on petroleum based fuels. Of these biofuels, Methyl-ester biodiesel holds significant potential as it has many characteristics similar to petroleum based diesel and can be blended with petroleum. However, biodiesel's differences in viscosity, specific energy, oxygen content, and cetane number can cause significant changes in engine performance and emissions. Therefore, it is of prime interest to understand the combustion behaviour of biodiesel and identify key factors that contribute changes in engine performance and emissions. In this study, a 100% biodiesel fuel derived from soy and an ultra low sulphur diesel fuel were tested in a high-speed direct-injection high pressure common rail four-cylinder 1.9L diesel engine. The engine control strategy allowed real time calibration and testing of independent control parameters including start of injection, injection duration, injection pressure, and exhaust gas recirculation (EGR) level. The engine was equipped with in-cylinder pressure transducers for combustion analysis. Instrumentation for gaseous emissions detection and carbaceous particulate matter (PM) sampling was also utilized. Both the fuels were studied under varied injection timing of 0centigrade BTDC to 12 centigrade BTDC in increments of 3 centigrade, EGR percentages of 0 and 10%, and injection pressures of 400 to 900 bar. Analysis was performed to determine the rate of heat release, ignition delay, NOX and PM emissions

Application and comparison of soy based biodiesel fuel to ultra low sulfur diesel fuel in a HPCR diesel engine - part I: engine performance parameters

In the US transportation sector uses two-thirds of the country's total oil consumption. In order to minimize the consumption in this sector there is a need to investigate alternate sources of energy. Biodiesel is a possible alternative to conventional diesel. Biodiesel has many characteristics similar to petroleum based diesel and can be blended with petroleum. However biodiesel's differences in fuel properties including viscosity, bulk modulus, density, and energy content can have significant impacts on engine performance parameters like BSFC and thermal efficiency. As the availability of biodiesel fuel increases, the need for engines capable of running on various mixtures of biodiesel fuel will be required. Similar to flex-fuel ethanol vehicles, control systems for the diesel engine and aftertreatment systems will need to detect and compensate for the fuel type. In this work, a soy based B100 biodiesel fuel and an ultra low sulfur diesel fuel were tested in a high-speed direct-injection high pressure common rail four-cylinder 1.9 L diesel engine. An internally developed engine control strategy allowed real-time calibration and testing of independent control parameters including start of injection, injection duration, injection pressure, and exhaust gas recirculation (EGR) level. Both the fuels were studied under varied injection timing (0°BTDC to 12°BTDC with increments of 3°) and EGR percentages of 0 and 10%. Analysis was performed to determine the Torque, BSFC and Brake thermal efficiency