【摘要】 针对高压共轨柴油机试验研究了不同转速及燃料种类下带催化剂涂层的微粒捕集器(DPF)安装前后的微粒粒度分布特征,分析了PDF对于不同粒径超细微粒捕集效率的影响规律。研究结果表明:燃用石化柴油和生物柴油(BTL)时,DPF安装前后微粒数量浓度分布曲线均呈双峰结构;DPF对微粒的捕集效率与发动机的转速及粒度分布特征相关,其对核态及超细微粒的捕集效果较好;中、小负荷工况下,DPF对超细微粒的捕集效率均达75%以上,随转速、负荷增加,对不同模态微粒的捕集效率降低,同时高捕集效率所对应的微粒粒径减小;与石化柴油相比,发动机燃用BTL时排气微粒中核态微粒所占比例较大,DPF具有较高的微粒捕集效率,尤其在大负荷工况下捕集效率明显高于石化柴油。更多还原

【Abstract】 The particle size distribution characteristics in a common-rail diesel engine with and without catalyzed Diesel Particulate Filter(DPF)under different fuels and operation conditions were studied by experiments.The filtration efficiency of catalyzed DPF for different particle sizes was analyzed.Results show that the exhausted particle concentration distribution curve presents bimodal structure when burning BTL and petroleum diesel with and without DPF.The DPF filtration efficiency is related to engine operation conditions and particle size distribution characteristics that the trapping effect is better for nucleation mode and ultrafine particles.DPF filtration efficiency for ultrafine particles can reach 75% under medium and low loads.As the speed and load increase the efficiency gradually decreases for different modal particles,and as the particle size decreases the efficiency increases.Compared with burning petroleum diesel,the exhausted particles are mainly in nucleation mode when burning BTL.BTL has higher filtration efficiency than petroleum diesel,especially under heavy load condition.更多还原