基于正交分析的柴油机微粒捕集器结构仿真优化

采用微粒捕集器可大幅减少船舶柴油机颗粒物的排放量,但在实际应用中仍然受到背压过大等条件的限制。文章利用GT-Power软件建立了柴油机和微粒捕集器(DPF)联合仿真模型,在柴油机试验台架上进行了模型验证试验,模型误差均在5%以内,满足仿真优化要求。分析了滤体结构中的微孔直径、壁厚、孔隙率、过滤体长度、通道密度对DPF性能的影响,可得微孔直径对捕集效率影响较大;壁厚和孔隙率增加时,过滤体压降和捕集效率均有所增加;过滤体长度和通道密度增加时,压降降低,初始捕集效率升高。通过正交分析法建立正交表并计算得出最佳DPF结构模型。与原模型相比,改进的模型压降由原来的7.16 k Pa下降至3.92 k Pa,初始捕集效率由原来的93.87%上升到94.09%,为DPF结构优化设计提供了理论依据。

Simulation and Optimization Research of Diesel Particulate Filter Structure Based on Orthogonal Analysis

In order to reduce the particulate matter emission of diesel engine greatly and meet the national V emission standard, a combined simulation model of diesel engine and particulate filter (DPF) was established by GT-Power software. The model validation test was carried out on the diesel engine test bench. The model error was less than 5%, which met the simulation optimization requirements. Firstly, the influence of micropore diameter, wall thickness, porosity, filter length and channel density on DPF performance is analyzed. The micropore diameter has a great influence on the capture efficiency. When the wall thickness and porosity increase, the pressure drop and capture efficiency of the filter increase; when the filter length and channel density increase, the pressure drop decreases and the initial capture efficiency increases. Secondly, the orthogonal table is established by the orthogonal analysis method and the optimal DPF structure model is obtained. Compared with the original model, the pressure drop of the improved model decreases from 7.16 kPa to 3.92 kPa, and the initial capture efficiency increases from 93.87% to 94.09%. This provides a theoretical basis for the optimal design of DPF structure.