基于多孔介质理论，采用标准k??湍流模型对不同结构的宏观蜂窝状空气滤清器的内部流场和阻力特性进行数值模拟，从而进行结构优化，提高其性能。采用的模型为相同滤芯(褶高h=5 mm)，壳体进出口形状分别为圆形与圆形(方案1)、圆形与椭圆形(方案2)、椭圆形与圆形(方案3)和椭圆形与椭圆形(方案4)的组合；优化得到的壳体结构与褶高分别为5, 10, 15 mm的蜂窝状滤芯组合，研究其过滤性能。结果表明，方案2的流场分布更均匀；压降随流量变大近似呈线性增长，当流量小于额定流量的60%时，4种方案的压降大致相等，大于额定流量的60%时，方案2的压降比方案1, 3和4小，方案2的壳体结构较合理。方案2滤芯褶高对空气滤清器流场分布有一定影响，且在研究的褶高范围内压降先降低后增加，存在最佳褶高使空气滤清器的压降最小。
Air filter as the heart of the car filtering the dirty air entering the engine which plays a key role in protecting the engine. In this work, because the performance of the air filter has a direct impact on the engine's power performance and economy, a standard k?? turbulence model was used to simulate the internal flow field and resistance characteristics of macrohoneycomb air filters with different structures based on the theory of porous media, thus to optimized the structure and improved its performance. The model adopted the same filter element(pleat height h=5 mm), while the series of combinations of the inlet and outlet shapes of the housing were round and round (scheme 1), round and ellipse (scheme 2), ellipse and round (scheme 3), ellipse and ellipse (scheme 4), respectively. Then the optimized housing was combined with honeycomb filter element with pleat heights of 5, 10 and 15 mm. The results showed that the flow field distribution of scheme 2 was more uniform than that of schemes 1, 3 and 4, and the pressure drop increased approximately linearly with the increase of flow rate. When the flow rate was less than 60% of the rated flow, the values of pressure drop of these four schemes were approximately equal. However, the pressure drop of scheme 2 was smaller than that of schemes1, 3 and 4 when the flow rate was greater than 60% of the rated flow. Therefore, the housing of scheme 2 was more reasonable. For this structure, the difference in the pleat height of the filter element had a certain influence on the flow filed distribution of the air filter. Furthermore, the pressure drop decreased firstly and then increased in the range of pleat height studied. Therefore, there was an optimal pleat height to minimize the pressure drop of the honeycomb air filter, which provided theoretical guidance for the optimal design of air filter.
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