柴油机DPF压降及噪声特性分析

Analysis of DPF Pressure Drop and Noise Characteristics of Diesel Engine

为探究发动机运行过程中DPF压降和噪声特性,本文中通过建立加装DPF的一维整机仿真模型,分析载体结构、碳载量、灰分量等因素对DPF性能的影响。结果表明:载体圆径尺寸越小,DPF压降越大,但噪声量相对减少,而载体长度对压降和噪声的影响甚微;碳载量越大,DPF排气端噪声越小;碳载量在4 g/L范围内时,深层过滤压降占DPF压降主导地位;碳载量超过4 g/L,碳烟层压降逐渐占据主导;灰分量与灰分分布系数大小对DPF压降和排气噪声影响效果相似,随其数值增长,压降增大,对噪声衰减能力增强。通过揭示载体尺寸、碳载量和灰分等因素对DPF压降及排气噪声特性的影响规律,为减少压降损失、降低排气噪声的DPF结构设计提供参考。

In order to explore the characteristics of DPF pressure drop and noise during engine operation,this paper analyzes the influence of carrier structure,carbon load,ash content and other factors on DPF performance by establishing a one-dimensional simulation model of DPF.The results show that the smaller diameter of the DPF carrier is,the greater the DPF pressure drop is,while the noise is relatively reduced,with little effect of the carrier length on the pressure drop and noise.The larger the carbon load is,the smaller the noise at the exhaust end of DPF is.When the carbon load is within the range of 4g/L,the pressure drop of deep filtration takes the dominant position.When the carbon load is more than 4g/L,the pressure drop of soot layer gradually dominates.The effect of ash content and ash distribution coefficient on DPF pressure drop and exhaust noise is similar.With the increase of the value,the DPF pressure drop increases and the noise attenuation ability increases.By revealing the influence of carrier size,carbon load and ash content on DPF pressure drop and exhaust noise characteristics,this paper provides a reference for DPF structure design to reduce pressure drop loss and exhaust noise.