Performance Experimental Research And Simulation Analysis On Pulse Cleaning Bag Filters

The study of bag filters includes experimental researches and physical simulation, but there is much certain limitation in the experimental study, such as a long period, can not monitor the actual working conditions of the dust stream filtration process as well as the cleaning process. What’s more, it is not deal with various effects and coupling relationship between cleaning mechanism and the ash removal mechanism factors, which restrict the development of its new product and the design innovation. Numerical simulation is difficult to determine the accurate boundary conditions, leading to discrepancies between simulation results and actual working condition. As a branch of simulation technology, semi-physical simulation combines the physical model with entity structure, which makes the simulation more close to the actual situation and receive more precise information.Pulse-jet cleaning has become the mainstream industrial air cleaning method of the bag filters. Though many documents studied on the cleaning mechanism and performance evaluation, it has not yet formed a mainstream consensus, meanwhile, the design of the pulse-jet cleaning filter excessive depend on expert’s experience, that limits the technical performance optimization and product innovation of pulse-jet cleaning filter.Therefore, to solve these problems, experiment, physics simulation and semi-physical simulation were combined in this paper. The research contents and results were as follows:(1) On the basis of collecting the research about bag house performance and numerical simulation, designed a multi-function integrated experimental device which takes into account the physical experiment and a semi-physical simulation experiment; completed the overall design of experimental system,experimental design and equipment selection; according to the literature summary, determined the experiment of the filter and effect evaluation index and the experiment value range of relevant parameters, built a semi-physical experiment hardware in the loop simulation system.(2) To ensure the experiment dust stream, designed a vibration device for dust transport, meanwhile, theoretical analysis and dynamic analysis have been done to verify the device is safe and the results quite meets the test requirements. The dust filtration experiments have been done to obtain the relationship between filter bag permeability and the time, which can lead to build a data interface of semi-physical simulation.(3) A simulation study on the filter system has been investigated, then a parametric mathematical model correspond to experimental device and a dust air filter pressure drop model combining the UDF function of fluent have been established. Combined with the response surface methodology, the influence between different lengths bag, filtration rate, dust concentration, filtration area to filter pressure drop and cleaning cycle have been studied. The findings provided a predictions of filter performance under experimental conditions.(4) A simulation study on the cleaning system has been investigated, then a parametric mathematical model correspond to experimental device is established. Combining the UDF function of fluent, the change of pulse valve outlet total pressure with time has been achieved. The pressure drop of filter bag, filter medium acceleration is selected as evaluation parameters, then, to obtained the optimum combination of tube and different modes of injection nozzle, provided a predictions of pulse-jet cleaning performance under experimental conditions.