The Study On Flow Field Of Dust Collection Devices And Its Numerical Simulation In Hot-dip Galvanizing

In recent years, with the country increasingly pay attention to the energy conservation and emission reduction, many enterprises are trying to save energy and reduce pollution from all sides. Undoubtedly, the key work is to effectively control and dispose dust when galvanizing to undertake hot-dip industry enterprise. However, domestic and foreign still don’t have a perfect technology and equipment for it at present.In this paper, proceeding from practice conditions of the hot-dip galvanizing process, and aiming at the advantages and disadvantages of the existing ventilation way at home and abroad, then combining with the ventilation and air conditioning theory, it is to do the structure design and related calculation for the blow-suction dust collection device. And then doing the improvement for the ventilation mouth of existing blow suction ventilation hood combined with the actual working conditions, eventually get the homogeneous air supply ducts and the balanced air suction ducts which are more adapt to the actual working conditions. Then this paper does a targeted theoretical research for the device flow field combined with computational fluid dynamics. Next this paper does a simulated calculation and analysis by FLUENT software respectively for the flow field of homogeneous air supply ducts, balanced air suction ducts and blow suction ventilation hood. Finally, this paper verifies the feasibility of collecting device by model experiments. And then the simulation results and experimental results are compared and analyzed.In structure design of the device, adopting assumption velocity method and combining with design principle of homogeneous air supply ducts and the basic condition of doing homogeneous air supply. And finally, in order to effectively control the flow of smoke and dust, this paper analyses and determines that the uniform air curtain can be formed by variable cross section ventilation ducts. In this paper we simulate and analyze the velocity distribution, vector filed and streamline of the different blow-off nozzle position, the different suction outlet position and the height difference between blow-off nozzle and suction outlet with a commercial FLUENT software. The simulation results show that while the blow-off nozzle position is located in the top position and suction outlet position is located in the intermediate position, the formation of the balanced ventilation and air curtain is the most favorable. When the height difference between blow-off nozzle and suction outlet is0.1～0.2m and blowing mouth speed is10m/s for1.5m wide zinc pot, this device collection results are satisfactory. And the effects on the whole collection by particle size is little. Finally, this paper does a model experiment and it shows that the simulation results are basically the same with the practical work, and the device collection can realize the purpose of uniform air distribution and collecting dust effectively.This paper indicated that a set of relatively perfect design ideas and guidance can be provided by discussion and analysis, design and calculation, computer simulation and model experiment above for the dust collection devices in hot-dip galvanizing. And the problem of exhaust gas dust collection has been resolved in hot dip galvanizing industry. The research of this paper also has a reference value significance to the dust removal by ventilation industry.