Experimental Study And Numerical Simulation Of Internal Airflow Distribution In Cartridge Filter And Its Structural Optimization

With air pollution problem increasingly prominent,it is urgent to better control the dust emission.Cartridge filter is a new high efficiency developed on the basis of bag filter,which has small volume,high efficiency and many other advantages,now widely used in various industries.Found in engineering application,the airflow distribution inside the cartridge filter has a great influence to the result of dust collection and filter cartridge life;however,the domestic and foreign scholars research in this aspect rarely,the study that how to improve the uniformity of airflow distribution inside the cartridge filter has the practical engineering significance.This paper has introduced the structure and material of cartridge filter,dust removal mechanism,purge mode and the classification of the cartridge filter to better understand the cartridge filter;test and record the performance of the relevant parameters of the cartridge filter based on the experimental platform.Test results showed that the initial inside and outside differential pressure of 39.8 Pa,initial filtration efficiency at about 98%,after pulse blowing dust,filter cartridge inside and outside differential pressure and filtration efficiency are improved than before;and the problem found in the testing process that internal flow field disorder in cartridge filter.For the phenomenon of uneven airflow distribution inside the cartridge filter,based on computational fluid dynamics simulation software “Fluent” to establish numerical model,and used the test data setting boundary conditions to analog computation.The flow field simulation results show that the relative mean square error value of velocity inside the cartridge filter is 0.43,the flow field uniformity is poor.For outlet direction and height position of cartridge filter,simulate and analysis the airflow distribution inside the filter cartridge,results show that the airflow distribution of the 4thoutlet patternis the best,Maximum flow unequal amplitude and Comprehensive uneven flow amplitude reached 0.1887 and 0.1887 respectively,airflow distribution is not uniform,there are the obvious phenomenon of jet flow and filter cartridge surface wind speed oversize.As the height of the outlet position increases,the airflow distribution in the filter tends to be even.For the problem that excessive wind speed on the surface of the filter cartridge,Change the spacing of the filter cartridges d(400mm,420 mm,440mm,460 mm,480mm),Analog display that as the spacing of the filter cartridges increased,the maximum flow unequal amplitude and comprehensive uneven flow amplitude of the filter decrease and then increase,and when the d = 440 mm,the internal airflow distribution of the filter is the best condition.The maximum flow unequal amplitude and comprehensive uneven flow amplitude of the filter of the 4thoutlet pattern reached 0.1475 and 0.043 respectively,the airflow distribution is basically uniform,but the airflow distribution of the other outlet patterns is uneven.In general,changing the spacing of the filter cartridges effectively improves the situation of excessive wind speed on the surface of the filter cartridge and between the filter cartridges,however,the improvementof the airflow distribution of the filter is limited.For the situation that obvious jet-flow exists in the inlet of cartridge filter,adopt the optimize measure of equal area double inlet.Analog display that the situation of jet-flow effective improvement,the maximum surface wind speed of the filter cartridge is also greatly reduced;the maximum flow unequal amplitude of 4outlet pattern models was reduced by 63%?63%?58% and 33% respectively;comprehensive uneven flow amplitude of 4outlet pattern models was reduced by 64%?68%?56% and 47% respectively;the internal flow distribution of the filter is basically uniform.