褶高和褶数对褶皱滤袋过滤风速分布的影响

Influence of Pleat Height and Number of Pleats on the Distribution of Filtration Velocity in Pleated Filter Bags

为获得褶皱滤袋过滤风速分布特征,采用数值模拟方法分析对比了袋长、褶高、褶数对褶皱滤袋过滤风速均匀性的影响,并通过减小袋口处褶高和滤袋顶部渗透率的方法来调整风速分布的均匀性。结果表明,袋长为4、6、8 m的褶皱滤袋风速从滤袋顶部1/3处开始迅速升高,8 m长滤袋顶部过滤风速呈指数增长,袋口处阻力值明显大于袋底处阻力值;随着滤袋褶高的增加,气体通过滤袋的阻力变大,滤袋整体过滤风速分布更加不均匀;相同处理风量下,褶数越多滤袋阻力值越大,过滤风速分布越不均匀;减小滤袋局部渗透率能显著提高过滤风速分布均匀性,但过小的渗透率会导致滤袋阻力的增加;减小袋口处褶高不仅能提高过滤风速分布的均匀性,同时也降低了滤袋的阻力值。

In order to analyse the problem of uneven distribution of axial filtration velocity of pleated filter bag,numerical simulation method was used to analyse and compare the effects of bag length,pleat height and number of pleats on the uniformity of filtration velocity of pleated filter bag,and adjust the uniformity of velocity distribution by reducing the pleat height and permeability at the top of the filter bag.The results show that the bag length of 4,6 and 8 m pleated filter bag wind speed from the top 1/3 of the bag began to rise rapidly.The top of the 8 m-long bag filtration wind speed was an exponential increase in the resistance value at the mouth of the bag,which is significantly greater than the resistance value at the bottom of the bag.With the increase in pleat height of the filter bag,the resistance of the gas through the filter bag becomes larger,and the overall filtration air velocity distribution of the filter bag is more uneven.Under the same processing air volume,the more pleats,the greater the resistance value of the bag,and the more uneven the distribution of filtering air velocity.Reducing the local permeability of the filter bag can significantly improve the uniformity of the distribution of filtering air velocity,but too small a permeability will lead to an increase in the resistance of the filter bag.Reducing the pleat height at the mouth of the bag not only improves the uniformity of the distribution of filtered air velocity but also reduces the resistance value of the bag.