多针头静电驻极熔喷布电场仿真及其过滤性能研究

Study on electric field simulation of multi-needle electrostatic electret treated melt-blown fabric and its filtration performance

为获得场强分布均匀且场强值较高的最佳多针头静电驻极结构参数,采用有限元模拟方法,研究驻极多针头与辅助电极等结构参数对场强分布的影响。利用COMSOL Multiphysics软件对多针头静电驻极过程中场强分布规律进行仿真,再通过优化后的多针头驻极装置测试熔喷布的驻极性能及过滤性能,并对其进行验证。结果表明:当电压25 kV、接收距离120 mm、针头直径0.5 mm、针长30 mm、针间距30 mm、高度差5 mm、辅助电极长度36 mm、辅助电极与相邻针水平距离28 mm、多针头曲率为3时,场强CV值为0.17%,消除了多针头驻极边缘效应。当电压25 kV、驻极时间20 min时,过滤效率较优,为93.45%,过滤阻力为84.5 Pa。认为:经过多针头静电驻极后,熔喷布过滤效率和阻力的不匀得到显著改善。

In order to obtain optimized structural parameters of multi-needle electrostatic electret electrode with uniform field strength distribution and high field strength value,finite element simulation was used to study the effects of structure parameters like multi-needle and auxiliary electrodes on the field strength distribution.COMSOL Multiphysics software was used to simulate the field strength distribution principle during multi-needle electrostatic electret process.The electret performance and filtration performance of melt-blown fabric were tested and verified through the optimized multi-needle electret electrode device.The results showed when the voltage was 25 kV,the receiving distance was 120 mm,the needle diameter was 0.5 mm,the needle length was 30 mm,the needle spacing was 30 mm,the height difference was 5 mm,the auxiliary electrode length was 36 mm,the horizontal distance between auxiliary electrode and neighbouring electrode was 28 mm,the multi-needle curvature was 3,the CV value of field strength was 0.17%,and the edge effect of multi-needle electrostatic electret was eliminated.The filtration efficiency was optimized to 93.45%and the filtration resistance was 84.5 Pa when the voltage was 25 kV and the electret time was 20 min.It is considered that the uneven filtration efficiency and resistance of the melt-blown fabric were significantly improved after multi-needle electrostatic electret treatment.