| Due to Bag filter has high collection efficiency,especially for fine dust particles also maintained a significant advantage of high removal efficiency,it became dusty gas purification most widely removal equipment.However,research and exploration on the realization of a simple structure of cleaning system,excellent cleaning effect of the new cleaning methods has been an important topic of bag filter research.In this paper,we study the process of filtering and cleaning of the new filter by numerical simulation method:Numerical simulation on process of filtering and scouring self-cleaning by dust airflow in transfixion bag filter.In order to reveal the dust stream erosion and cleaning perforation filter bag at the time of filtration state that air flow field and the trajectory of dust particles;And the cleaning process of the release of dust pellet that settling trajectory in the hopper.At the first,using FLUENT software to modeling for object,then meshing,finally initialized.Based on this,At the first,for the dust stream that in thong filter bag do the simulate the process.The simulation results show,since the filter bag and the dust layer have a large resistance,the axial pressure and axial radial velocity distribution substantially uniform within the bag,the axial velocity on the section showed a typical parabolic distribution and top-down gradually decreases;Due to the inertia force of the dust particles,larger particles exhibit out of the airflow an went to the bottom of the bag at the different degrees.Particle diameter exceeds 20μm of the dust at the center of the bag mouth can be directly fall below the projection hopper.when scour cleaning,the simulation showed that the dust pellets of stripped from the outlet of through bag and following the airflow settlement with the cleaning track in the hopper,when the filtration velocity of lm/min the settling efficiency of hopper will be increased as the addition of the hopper flow cross-section,when the hopper height is at the range of 0.9m～1.6m the settling efficiency increases with the height of the hopper have a big margin;When the hopper height exceeding 1.6m the settling efficiency increases with height hopper have a amplitude decreases,and when the hopper height of 2.3m settling efficiency has reached 81.42 percent,then increase the height of hopper the settling efficiency does not increase.When hold the hopper height and density change dust pellets diameter,the settling efficiency will increases with the increases of dust pellets,when the dust particle size in the range of 5μm to 30μm,the hopper settling efficiency will increases with increasing of particle size,but have a low trend.When the dust particle size of 40μm the settling efficiency can reach almost 80%;When hold hopper height and dust size,when changing the density of dust settling efficiency will increase as the dust density increases,when the hopper height of 1.3 meters,with the dust pellet density increases the settling efficiency have a slow increase,when the hopper height of 1.8 meters and 2.3 meters the settling efficiency increased by a big margin.The simulation results demonstrating that new precipitator filtration and cleaning conditions during dust collection and stripped settlement feature,Basically consistent with experimental results that related to experimental research models.It confirmed that the new precipitator has a low load,cleaning effective,simple structure of outstanding merit. |
