基于GT-Power的车用催化器消声特性研究

Study on Noise Characteristics of Vehicle Catalytic Converters

对一款车用催化器的消声特性进行了试验测试和仿真研究。利用白噪声测试法获得其传声损失,基于GT-Power软件实现了对其声学性能的仿真分析。试验结果表明催化器具有明显的消声频段和通过噪声,峰值消声量可达到20dB;与催化器孔隙率相等的单管催化器模型传声损失曲线形状与试验结果接近,但消声量偏低;催化器载体的孔隙率以及管径、管数对传声损失有重要影响;双床催化器较单床催化器传声损失有较大提高,两级催化器较单级催化器传声损失也有很大的提高,消声特性改善明显。

This article conducts an experiment test and simulation researches on one section of vehicle catalytic converters.Using white noise test method to obtain its transmission loss and realizing simulation analysis of its sound characteristics based on GT-Power software.Experimental results show that catalytic converters have obvious silencer band and pass-by noise.The top sound attenuation reaches 20 dB.The transmission plot of single-pipe model which has the same porosity with the converter is close to the experimental plot,however,with lower attenuation.The porosity,number and diameter of pipes in the carrier have important influence on transmission loss.Double bed converter has higher TL than single bed.TL of double level converters also increases a lot than single level,which improves sound attenuation obviously.