Study On The Flow Field Characteristic In The Filtration And Dust-Cleaning Process Of The Bag Filter With Numerical Simulation

Bag filter mainly includes two systems:Filtration and Dust-cleaning. Only filteration and dust-cleaning alternating continuously can form a complete dust-removal process. The flow field characteristic in the filtration and dust-cleaning process of the bag filter directly influence dust-removal efficiency, dust-cleaning efficiency, filter bag life and equipment energy consumption. There are many factors influence the flow field characteristic of the filtration and dust-cleaning stage. Domestic and foreign scholars mainly use the physics experiment and numerical simulation to study the flow field characteristic of the filtration and dust-cleaning stage, try to find the influence rule how do the factors influence the flow field distribution, provide technical support to product innovation and develop new bag filter with market competitiveness.In the filteration process, dust laden gas enters into the individual compartments cotaining the filter bags. The dust laden gas is cleaned as it passes from the outside of the filter bags to the inside then out through the top. During this process, the dust is deposited on the outside of the filter bags. The gas-solid two-phase flow field in the individual compartments cotaining the filter bags is complex. The dust builds up and forms a cake on the outside of the filter bags which increases the pressure drop of the filter and must be cleaned periodically. In the dust-cleaning process, a short, high intensity, impulsive flow enters into the inside of bag from the outlet of nozzle of the injection pipe. It can increase the pressure in the filter bag quickly and accelerate the filter bag outwards and propel the dust cake off the filter bag. The3D unsteady flow field in the injection pipe and filter bag is complex and the flexible filter bag deformates random under the pulse-jet cleaning flow. Therefore, to develop competitive bag filter, We must study the gas phase flow field distribution characteristics, the dust particle movement in compartments cotaining the filter bags during the filteration process and unsteady flow field distribution characteristics in the ingection pipe&filter bag, the filter bag dynamic response during the dust-cleaning process. This paper mainly study the flow field distribution characteristics during the filteration process and dust-cleaning process using numerical simulation method based on the computational fluid dynamics (CFD) and calculating structure dynamics(CSD). At the same time, how do the structure type of bag room, the inlet air way, the flow-leading device, the injection pipe type, the inlet flow of injection pipe, filter material characteristics and venture influence the flow field distribution characteristics during the filteration process and dust-cleaning process.