| Energy crisis and environmental pollution are serious challenges for thedevelopment of internal combustion engines. Seeking for new high-efficiency andclean combustion methods becomes the key to meet future diesel engine emissionregulations. Low-temperature combustion (LTC) has the potential to achieve highefficiency combustion and ultra low emissions at the same time. Fuel propertiesbetween diesel and gasoline are more suitable for the LTC in a wide range ofoperating conditions. In this paper, Gasoline and diesel were blended aswide-distillation fuel, and experimental study on fuel properties of wide-distillationfuel on LTC mechanism were conducted on a single-cylinder diesel engine. Theeffects of fuel volatility on LTC were studied further.At20%and40%gasoline blend ratios, experimental study on the effects ofdiesel/gasoline wide-distillation fuel on LTC was conducted. The results show thatcetane number played a dominant role in the LTC combustion characteristics. Withthe EGR rate increased and load reduced, effects of Wide-Distillation Fuel on theLTC combustion characteristics are more significant. With the gasoline blend ratioincreased, indicated thermal efficiencies of wide-distillation fuel increased slightly.Wide-distillation fuel with a higher proportion of gasoline has lower soot emission.Effects of fuel volatility on LTC were studied in different blend ratio ofdiesel/n-heptane blending fuels. With the improvement of volatility, soot emissionsare significantly reduced, while cetane number still plays a dominant role in the LTCcombustion characteristics. Appropriate increased injection pressure is an effectiveway of reducing soot emissions and improving thermal efficiency on LTC. In addition,improving fuel volatility reduced the demand for high injection pressure.The wide-distillation fuel, fuel volatility and injection pressure had littleinfluence on NOxemissions. CO and THC emissions remained as a problem to besolved for wide-distillation fuel LTC. |
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