Research On Wind Velocity Control System Of Composite Particulate Collector

Based on analyzing the available experience of the traditional cyclone separator,a new type of cyclone-bag composite precipitator was introduced.The device makes combination of two kinds of dust removal mechanism,which has certain significance of scientific research and application.Big-density particles are removed by cyclone and small-density particles removed by filtration,by this way,the application range of ordinary cyclone device is widened.An wind velocity control system relevantly was designed to ameliorate the deficiency of cyclone's low efficiency for fine particle and low intelligent level.At the same time,The flow field of this machine under different wind velocity was simulated to explore its capacity of classification processing to the dust.The main contents of this thesis are as follows:(1)According to the structure characteristics of this device and the complexity of dust removal operation,an air-intake system was designed based on the principle of energy saving of frequency control,to adjust the pressure difference between the inlet and outlet.Then,a Fuzzy-PID control algorithm was chosen and built to control the dust removal system,which was described with detail by MATLAB after compared with conventional PID control and single fuzzy control method.The comparison results of simulation show that the fuzzy-PID has an excellent control performance in both of the dynamic and static response characteristics.(2)The flow field of the hybrid particulate collector under the condition of different inlet velocity was simulated by FLUENT software.The physical model was built by GAMBIT2.4.6,and in order to get more ideal results,the RSM numerical simulation method was adopted on the premise of good grid partitioning.The simulation results show that: The flow field in the composite dust collector is stable and a better symmetry has been displayed.The number of local turbulence is reduced,especially,the radial velocity field is less affected by the inlet velocity,which prove that the control method is feasible.Besides,the two-phase flow field of the equipment was simulated to explore the effects of air velocity on trajectories of size-fractionated particulates.(3)The experiment system was built with the SIEMENS S7-200 PLC as the core to research the stability and separation performance of the composite separator.The results show that: the removal efficiency of composite machine for the dust,which median diameter size were 3 ?8 and 17?m,could reach to 99% under different inlet wind speed.The particle collection efficiency between 1?m and 5?m was increased compared to the conventional cyclone separator.Besides,the separation efficiency of the cyclone in the composite dust removal efficiency of 5?m was increased from 41% to 53% when the inlet velocity increased from 12m/s to 16m/s.In this thesis,the stability,rationality and feasibility of the system are verified by algorithm and flow field simulation,and the dust removal capability has been studied by experimental research.In a word,the system and the device as a whole can cope with the complex changes in dust conditions.The studies will be assistant for the further research of this machine in the future.