中文摘要：

为了有效降低柴油机微粒捕集器DPF压降,通过建立DPF灰分模型和压降模型,运用数值计算的方法研究了非对称孔道DPF的压降特性及其影响因素.研究结果表明：增大DPF进、出口孔道直径比,进口孔道排气流速减小,孔道壁面前端渗流速度减小,孔道壁面后端渗流速度增大,排气流经出口孔道流速增大;增大DPF进、出口孔道直径比能降低DPF压降;随着碳载量、灰分量以及排气流量的增大,增大DPF进、出口孔道直径比对降低DPF压降效果更加明显;孔密度最优值随进、出口孔道直径比增大而减小.

英文摘要：

The asymmetric diesel particulate filter pressure drop characteristics and its influencing factors were studied numerically through establishing diesel particulate filter ash and pressure drop models for the purpose of decreasing diesel particulate filter pressure drop effectively.Results show that,with the increase of ratio of inlet and outlet diameters,the inlet velocity and front wall velocity are decreased while the rear wall velocity and outlet velocity are increased.The pressure drop of diesel particulate filter decreases with the increase of the ratio of inlet and outlet diameters.The accretion of soot mass,ash mass and flux enhance the tendency.Optimal value of cell density decreases with the increase of the ratio of inlet and outlet diameters.