Effect of Injection Pressure and Timing of the Ternary Blends (Ethanol-Biodiesel-Diesel) on Combustion Characteristics

DOI: 10.14416/j.ind.tech.2023.08.003

Abstract

This research studies the combustion characteristics of a compression ignition engine when using ternary blends (ethanol-biodiesel-diesel). Because ethanol is renewable energy and can lower exhaust emissions, it is interesting to use in a diesel engine. With less effort to prepare the fuel and apply it in the engine, the blending technique is used in this research. However, phase separation readily occurs as the percentage of ethanol increases and at the low ambient temperature. Fortunately, biodiesel has been used commercially as a blend and can act as a surfactant to keep the phase stable. To comply with the market, the blend ratio used is B3E5, B7E5, and B10E10, where B stands for biodiesel, E is ethanol, and the numeric presents the percent of each fuel by volume. In addition, diesel adding 3 percent biodiesel as a lubricity enhancer is used as the reference. Combustion features such as heat release rate, ignition delay, and mass fraction burned derived from in-cylinder pressure are experimented with through a single-cylinder common-rail diesel engine. The injection pressure varies from 500, 700, and 1000 bar, while injection timing adjusts from 335, 340, 345, 350, and 355°CA. With ethanol concentration, the ignition commences earlier than diesel B3 due to the puffing phenomena. However, adding more biodiesel content results in later ignition because of the difficulty of the fuel-air mixing process. The high content of ethanol and biodiesel yields the lengthiest ignition delay.