【摘要】 研究了多点电喷汽油机燃用不同掺混比的乙醇-汽油混合燃料时的排放及催化器的转化性能。研究结果表明:在汽油机参数未做任何调整的情况下,随着乙醇-汽油混合燃料中乙醇含量的增加,催化器前的THC排放明显降低,最大降幅接近30%,但未燃乙醇和乙醛排放量增大。Pt/Rh系三效催化剂对乙醛的催化转化效率高,但对乙醇的催化转化效率低。乙醇对催化器前的CO和NOx排放及其催化转换效率的影响与电喷汽油机的转速、负荷和空燃比控制策略有关。此外,含30%(V)乙醇的汽油对改善电喷汽油机怠速时催化器前的THC,CO和NOx排放特别明显。更多还原

【Abstract】 In this paper,the effects of ethanol blended gasoline on emissions and catalytic conversion efficiency characterstics are investigated in a multiplepoint EFI gasoline engine without modification.The results show that with the increase of ethanol concentration in the blended fuels,engineout THC emissions are drastically reduced.The maximum improved level is up to thirty percent.However,engineout unburned ethanol and acetaldehyde emissions increase.Pt/Rh based threeway catalysts are effective to reduce acetaldehyde emissions,but have low catalyst efficiency for unburned ethanol conversion.The effect of ethanol on engineout CO and NOx emissions and catalytic conversion efficiency has relation to engine’s speed,load and air/fuel ratio.Futhermore,the fuels blended with thirty percent ethanol by volume can dramatically reduce engineout THC,CO and NOx emissions at idle speed.更多还原