汽油机掺醇燃烧甲醛排放及后处理适应性研究

进行了电喷汽油机燃用汽油和多种不同掺混比例甲醇汽油的试验研究,使用傅里叶红外光谱仪(FTIR)测量了普通三元催化器前后的甲醛排放。试验结果表明:甲醛排放量随掺醇比例、转速的增加而增大,随扭矩的增加先减少后增加;三元催化器对甲醛排放的催化转化效率随着掺醇比例的增加而减小;燃用M30以下低比例甲醇汽油时,催化器对甲醛排放的催化转化效率在多数工况都能达到85%以上,受工况影响并不明显;燃用M50以上中高比例甲醇汽油时催化器对甲醛排放的催化转化效率受工况影响较大,随着发动机转速、扭矩的增加而增加,在低转速低负荷下催化效率下降明显。

Formaldehyde Emission and Post-processing Adaptability of Gasoline Engine Fueled with Methanol-gasoline Blends

An EFI gasoline engine was fueled with pure gasoline and different methanol-gasoline blends and its formaldehyde emission before and after three-way catalyst was measured with a Fourier transform infrared spectroscopy(FTIR) device.The results show that the formaldehyde emission increases with the increase of methanol content and engine speed,and first decreases and then increases with the increase of torque.The conversion efficiency of formaldehyde decreases with the increase of methanol content.The mixing ratio of methanol is lower than M30,the conversion efficiency of formaldehyde can be more than 85% in most of conditions and is hardly influenced by the conditions.The mixing ratio of methanol is higher than M50,the conversion efficiency of formaldehyde is obviously influenced by engine conditions,increases with the increase of engine speed and torque,and significantly decreases at low speed and low load.