一种细水雾喷雾除尘装置除尘性能影响因素数值模拟

Numerical simulation of influence factors of dust removal performance of a fine water spray dust removal device

为探究细水雾喷雾除尘参数对除尘性能的影响,构建欧拉气相-欧拉粉尘-离散雾滴相耦合的3相流计算模型,同时考虑除尘过程中雾滴蒸发的影响,在气液固3相耦合基础上加入蒸发模型。将建立的模型与文献中的试验数据进行对比校验,数据偏差在15%内,表明所建模型可靠。基于建立的模型,开展了雾滴粒径、雾滴速度、尘域环境温度、风机风速等参数对除尘性能影响的模拟研究。结果表明:1)在模拟范围内,考虑雾滴蒸发综合作用影响下,较大雾滴粒径时,喷雾除尘效率随雾滴粒径的减小而增大,当雾滴粒径小于20μm时,喷雾除尘效率随雾滴粒径的减小而减小;2)喷雾除尘效率随雾滴速度的增大而增大,但当雾滴速度增加到25 m/s以上时,喷雾除尘效率随雾滴速度的增大而减小;3)喷雾除尘效率随尘域环境温度的升高而下降;4)喷雾除尘效率随风机风速的升高而下降。研究结果可为细水雾喷雾除尘装置的设计与使用提供理论参考。

To explore the influence of water mist spray dedusting parameters on dedusting performance,a simulation study on the dedusting performance of the spray dedusting process is carried out.In the simulation,the Euler multiphase flow model is turned on,the Realizable k-8 turbulence model is selected,the Syamlal-Obrien model is selected for the particle viscosity model,and the Lun-et-al model is selected for the particle volume viscosity model.A three-phase flow model of Euler gas phase-Euler dust phase-discrete droplet phase coupling is constructed.Besides,considering the influence of droplet evaporation on the process of spray dust removal,the evaporation model is added based on gas-liquid-solid coupling.To verify the reliability of the model method,it is verified with the experimental research data in the literature.The variation trend of experimental and simulation results is consistent,and the data deviation is within 15%.In this paper,the effects of droplet size,spray speed,ambient temperature,and wind speed of the fan on dust removal performance are simulated.The results show that in the simulated particle size range of 20-100μm,the efficiency of spray dust removal increases with the decrease of droplet size.When the droplet size decreases further,the efficiency of spray dust removal decreases.When the droplet velocity is less than 25 m/s,the efficiency of spray dedusting increases with the droplet velocity.When the droplet velocity is higher than this value,the efficiency decreases with the droplet velocity.The efficiency of spray dedusting decreases with the increase of ambient temperature in the dust domain.The eficiency of spray dedusting decreases with the increase of wind speed,while the comprehensive dust removal efficiency under the combined action of ventilation and spray increases with the increase of wind speed.The particle size of the spray droplet,spray speed,ambient temperature in the dust domain and wind speed of the fan have significant effects on dust removal performance.The research results can provide a theoretical reference for the design and use of water mist spray dust removal devices.