含水乙醇汽油对发动机排气噪声的影响研究

Research on the Effects of Moisture Ethanol-gasoline Blended Fuel on Engine Exhaust Noise

以一款1.5 L汽油机为研究对象,基于GT-Power搭建了发动机及排气系统模型并进行了标定,对燃用含水乙醇汽油(E10w/E20w/E30w/E40w/E50w)发动机的排气噪声进行了仿真计算,并对其中E10w/E30w含水乙醇汽油进行试验分析。结果表明:低转速下所搭模型能较好地反映含水乙醇汽油发动机排气噪声的性能,高转速时则存在误差;燃用含水乙醇汽油,能够显著降低3 000 r/min以下的排气噪声,且乙醇比例越高,排气噪声越低,最大下降10.3 d B(A),降幅为14.3%,而在3 000 r/min以上时,E10w的噪声略有升高;阶次噪声则不受转速影响,在各转速下均呈现乙醇含量增加,排气噪声降低的趋势。对于完善含水乙醇汽油性能评价具有实用价值。

Taking a 1.5 L gasoline engine as the research object,the engine and exhaust system model is built by GT-Power,and the model is calibrated.The exhaust noise of ethanol fueled gasoline（E10w/E20w/E30w/E40w/E50w）engine was simulated,and the experimental analysis of E10w/E30 w ethanol fueled gasoline was carried out.The result shows that the model can be used to reflect the performance of exhaust noise of ethanol gasoline engine at low speed,but there is a deviation in high speed condition;Using hydrous ethanol gasoline can significantly reduce the exhaust noise under 3 000 r/min,the higher the ethanol ratio,the lower the exhaust noise,the maximum drop value was 10.3 dB（A）,the decline reached 14.3%,however,when the speed is above 3 000 r/min,the noise of E10 w increases slightly.The order noise is not affected by the rotation speed,the exhaust noise decreases with the increase of ethanol content under each speed condition.