Internal Flow Field Simulation Research Of The Cis-Flow Bag Filter

At present,China has become one of the most serious air pollution in the world,especially in recent years,"smog" weather which can be inhaled particulates PM10 and PM2.5 etc.This phenomenon has brought a very serious impact to people's health.Most of the "smog" phenomenon which are derived from building materials,steel plants,thermal power plants and other industrial production of dust particles emissions.If such problems are not effectively governed,it will bring incredible consequences to mankind.With the deployment of national sustainable development strategy and the strengthening of people's environmental awareness,China's air pollutant emission standards become more stringent.Bag filter with its ultra-high dust efficiency and perfect to adapt to the advantages of various types of work conditions gradually become the key equipment which gover the industrial pollution sources.The effective use of bag filter control the dust particles pollutant emissions to a certain extent,but there are still many problems.Through the investigation and analysis of the practical use of the bag filter in all kinds of working conditions,it is found that the uniformity of the internal flow field of the bag filter seriously affects the running resistance of the equipment,the service life of the filter bag and the dust removal efficiency etc.As the bag filter during the operation,the internal air flow is closed and flow state is complex and irregular.This is cause difficult experimental analysis means to direct test and operability is not high.In this paper,the internal flow field distribution of the cis-flow bag filter is designed and studied.Applied Computational Fluid Dynamics(CFD)softwareresearch the Jiangsu enterprises bag filter which is up the wind into the flat filter bag.The influence of the bag filter internal flow field distribution with different inlet velocity conditions was studied.Based on the analysis of the main reasons for the damage of the filter bag and the filter bag is easy to break the location.Proposed a more reasonable inlet velocity range.The Euler-Lagrangian discrete item model provided by Fluent software was used to calculate the trajectory of dust particles in the cis-flow bag filter.The velocity field diagram of the internal airflow of the precipitator was obtained with different inlet velocity conditions(7m / s?9 m / s?11 m / s?13 m / s?15 m / s).Testing the velocity of the filter bag gap and RMS air distribution standards which can determine the different conditions of internal airflow uniformity.The operating resistance of the precipitator is analyzed by the maximum differential pressure inside the bag filter.It shows that the bag filter has less resistance with the uniformity of the better air flow conditions.For the individual parts of the bag is often the first case of damage,we test the filter bag area to handle air flow and contact the position of the filter bag gap maximum velocity which can direction and explain for the fragile filter bag.The simulation results show that the inlet velocity seriously affects the uniformity distribution of the internal airflow in the bag filter.When the air inlet velocity is large,there is obvious vortex in the upper and lower boxes.With the decrease of the air inlet velocity,the vortex intensity and area gradually decrease.It can be concluded that the flow field distribution is more uniform at 9 m/s and 7 m/s and the resistance during operation is smaller by introducing the RMS airflow criterion.On the basis of the air inlet velocity,Analysis of filter bag area to deal with air flow and contact the position of the filter bag gap maximum velocity.It shows that the area of B handle air flow load heavier and D handle air flow load minimal.The wearable parts of the filter bag can be predicted by the above results which can provide a reliable reference for the operation and maintenance of the bag filter.