Study on Combustion and Emission Characteristics of Diesel Engines Fueled with Ethanol/Diesel Blended Fuel

<div class="htmlview paragraph">The effects of different ethanol-diesel blended fuels on the performance and emissions of a single cylinder engine have been experimentally evaluated and compared in this study. Several diesel blends containing up to 20% ethanol have been operated on the IC engine and compared with the pure diesel fuel. The regulated and unregulated emissions have been measured, the regulated emissions were HC, CO, NOx and CO2, the unregulated emissions were formaldehyde(CH20), formic acid(HCOOH), acetaldehyde(CH3CHO) and ethanol(C2HsOH).</div> <div class="htmlview paragraph">Addition of ethanol in the fuel made an increase of ignition delay and burning phase lag, but had little effects on the largest pressure of cylinder. The emission tests indicated that NOx emissions declined with the increasing ethanol-containing, especially in high-speed and high-load conditions. For ethanol-containing fuels, HC emissions were appreciably increasing (up to 50%).CO emissions were extremely high under high load conditions.</div> <div class="htmlview paragraph">Fourier Transform Infrared spectroscopy(FTIR) and Gas Chromatography(GC) methods were used to investigate the characteristics of unregulated emissions from the tested engine. The results showed that diesel/ethanol fueled engine basically had higher formaldehyde, formic acid and acetaldehyde emissions than diesel fuel. The residual unburned ethanol can achieve approximately 30-40 ppm.</div>