应用计算流体力学方法对高温下的线板式静电除尘器进行数值模拟,建立综合考虑温度场、电场、流场和颗粒动力场的多场耦合模型。采用有限体积法对计算域进行离散进而求解电场,采用欧拉-拉格朗日方法求解气固两相流动。研究温度对于静电除尘器内颗粒受力的影响。结果表明:随着温度的升高,颗粒所受的静电力减小而Saffman升力、布朗力和曳力均增大;曳力随温度的增加速率比静电力变化快,这可能是导致高温下除尘效率降低的原因。
A computational fluid dynamics (CFD) model is proposed to describe the wire-plate electrostatic precipitator (ESP) in high temperature condition. In this model, the complex interactions among the electric field, temperature field, fluid dynamics, and the particulate flow are taken into account. The finite volume method is used to solve the electric field and the Euler-Lagrange model is used to describe particle-laden flows. The influences of high temperature on particle characteristics in ESP are investigated in the current simulation. Numerical results show that Coulomb force decreases while the Saffman lift force, Brownian force, and drag force increase with the temperature. Besides, the increasing rate of drag force is faster than that of Coulomb force, which may cause the reduced efficiencies at high temperature.
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