袋式除尘器内部流场的数值模拟

Numerical simulation of flow field in bag filter

袋式除尘器内部气流分布不均会加剧滤袋磨损,降低除尘效率。采用计算流体动力学(CFD)数值模拟方法对除尘器内部流场进行研究,分析了气流的轨迹及其在各气室中的速度分布。发现原设计中气流分布不均匀的现象比较明显,提出了在进气通道内添加气流均布板的改进措施。结果表明:改进后,除尘器箱体内部气流分布较均匀,各滤袋气流分配系数的波动幅度减小,各气室综合流量不均幅值降低。研究结果为袋式除尘器的结构优化设计提供了理论依据。

The nonuniform distribution of flow in bag filter will increase bags wear and decrease collection efficiency. The numerical simulation of filter internal flow field was carried out by using computation fluid dy- namics method. Analysis on the flow trajectories and velocities confirmed the nonuniform distribution of flow in prototype filter. As an improvement measure, airflow uniform plate was added in the passageway. The results show that the distribution of flow is more even in modified filter, the amplitudes of air partition coefficient in each bag and integrated uneven coefficient in each chamber are decreased simuhaneously. The research results provide the theoretical basis for the optimal structure design of bag filter.