不同海拔下柴油机颗粒过滤器碳烟加载及再生特性研究

为研究不同海拔下柴油机颗粒过滤器(diesel particulate filter,DPF)碳烟加载规律及再生特性,在一台高压共轨柴油机上分别在两种大气压力(80kPa和100kPa)下进行了试验研究。研究内容包括全球统一瞬态循环(world harmonized transient cycle,WHTC)排放测试、DPF碳烟加载及压降特性、DPF再生过程温度场及压降特性。结果表明:高原环境下DPF的排气温度和各项排放数据指标均高于平原环境。高原环境下压降损失随碳烟的累积呈现出先快速增加后缓慢增加的趋势。再生温度和海拔高度对DPF再生压降、载体再生峰值温度、载体再生径向和轴向温度梯度、再生时机均有影响;再生温度越高及海拔越低,DPF再生压降越高;再生温度及海拔越高,再生时载体的峰值温度越高且载体径向和轴向温度梯度越大。

Study on Soot Loading and Regeneration Characteristics of Diesel Particulate Filter at Different Altitude Levels

In order to study the soot loading law and regeneration characteristics of diesel particulate filter (DPF) at different altitudes, a research was conducted under two atmospheric pressures (80KPa and 100KPa) on a high pressure common rail diesel engine, which included the world harmonized transient cycle (WHTC) emission test; the DPF soot loading and pressure drop characteristics test; the temperature field and pressure drop characteristics of the DPF regeneration process test. The results showed that the DPF exhaust temperature and emission data in plateau environment were higher than that in plain environment, and the exhaust flow and oxygen concentration were higher in plain environment than that in plateau environment. The pressure drop loss increased rapidly at first and then slowly with the cumulation of soot at high altitude. The regeneration temperature and altitude had influence on the regeneration pressure drop of the DPF, the peak temperature of the carrier regeneration, the radial and axial temperature gradient of the carrier regeneration and the regeneration time; the higher the regeneration temperature and the lower the altitude, the higher the DPF pressure drop; the higher the regeneration temperature and the higher the altitude, the higher the peak temperature of the carrier regeneration; the higher the regeneration temperature and the higher the altitude, the larger the radial and axial temperature gradient of the carrier regeneration; the higher the regeneration temperature and the lower the altitude, the higher the DPF pressure drop corresponding to the regeneration time.