【摘要】 基于D30TCI柴油机耦合氧化催化器(DOC)和柴油机颗粒捕集器(DPF)的试验台架,对3种不同结构DPF开展压降特性试验.并构建了DPF一维仿真模型及三维1/4孔道模型,研究了载体配比、载体孔密度对DPF压降及捕集特性的影响及载体配比及灰分沉积对DPF孔道内部气流运动及颗粒沉积特性的影响.结果表明:同一DPF配比下,提高载体孔密度能降低压降,且灰分增加能提升此效果;增大DPF配比有利于降低DPF压降并提高其捕集效率,结合成本与性能考虑,载体配比的最佳范围(1.2～1.5)使DPF压降及捕集特性达到最优,灰分加载不会影响配比对DPF压降的影响规律;无灰分时,DPF出口孔道压力沿DPF轴向方向逐渐均匀下降;有灰分沉积时,增大灰分分布系数可提高捕集效率,进口孔道颗粒浓度增大,且DPF配比增大能提升此效果.更多还原

【Abstract】 Based on a test bench of D30 TCI diesel engine coupled with oxidation catalyst(DOC)and diesel engine particle filter(DPF),the DPF pressure drop of three different structures of DPF were tested. A one-dimensional simulation model and a three-dimensional quarter channel model of DPF were constructed to study the effects of carrier ratio and carrier mesh number on characteristics of DPF pressure drop and trapping,and the effects of carrier ratio and ash deposition on flow movement and particle deposition characteristics inside DPF channels. The results show that under the same DPF ratio,increasing the number of carrier mesh can reduce the pressure drop,and increasing ash content can improve the effect. Increasing the DPF ratio is beneficial to reducing the DPF pressure drop and improving the collection efficiency. Considering the cost and performance,the optimal range of the carrier ratio(1.2—1.5)makes the DPF pressure drop and the collection efficiency to be optimal. The ash loading doesn’t affect the influence of the ratio on the DPF pressure drop. When there is no ash,the outlet pressure of DPF decreases uniformly along the axial direction of DPF. When there is ash deposition,increasing the ash distribution coefficient can improve the collection efficiency,and the particle concentration in the inlet channel increases,and increasing DPF ratio can improve the effect.更多还原