烟气旋流除尘装置性能的数值模拟及比较

Numerical Simulation and Comparison of Cyclone Flue Dust Separator Performance

对进出口段采用突变管、渐变管的两种烟气旋流除尘装置的压力损失、除尘效率以及烟尘微粒的运动轨迹进行了模拟和分析，采用Fluent6．1进行数值模拟计算。烟气旋流除尘装置的导流旋流叶轮压力损失很小，压力损失主要集中于进出口段。进出口段采用渐变管可降低压力损失，对除尘效率影响较小。对粒径为10μm及以上的烟尘微粒具有较高的除尘效率，对于链条炉排炉、振动炉排炉、抛煤机炉燃烧产生的烟气，总除尘效率大于96％。烟气旋流除尘装置的空筒速度宜为2．8-3．8m／s。烟气主要在筒体的前部被捕捉，因此筒体设计长度不宜太长，以免烟气微粒被二次夹带。

The pressure loss, dust removal efficiency and flue dust particle trajectory of two kinds of cyclone flue dust separators using sudden variable diameter tubes and gradual variable diameter tubes at the inlets and outlets are simulated and analyzed, and the numerical simulation calculation is carried out by Fluent 6.1. The pressure loss of cyclone impellers of cyclone flue dust separators is small, and the pressure loss takes place mainly at the inlets and outlets. Using gradual variable diameter tubes at the in-let and outlet can reduce pressure loss and has less influence on dust removal efficiency. The removal efficiency of flue dust particles with diameter of 10μm and over is higher. The total dust removal efficiency for the flue gas exhausted from chain grate stoker boiler, vibrating grate boiler and spreader stoker boiler is over 96%. The gas velocity in the empty separator cylinder should be 2.8 to 3.8 m/s. The flue gas is mainly captured near the inlet part of the cylinder, and to avoid the captured particles being carried away, the design length of the cylinder should not be too long.