基于数值模拟的除尘器入口烟道阻力特性研究

摘要

Geometric shape of precipitator inlet flue duct in thermal power generating units not only affects the uniformity of precipitator inlet air flow but also the resistance of the flue duct gas system. This paper uses two design schemes for the geometrical shape of flue duct from air preheater outlet to electrostatic precipitator inlet: one is conventional rectangular flue duct and the other is circular flue duct. Standard k-ε model is adopted, and SIMPLE algorithm is used for pressure-velocity coupling. Meanwhile, Fluent software is used for numerical simulate and calculation of flow filed of the flue duct. Additionally, the resistances of the flue duct in the above two conditions are analyzed and calculated. The calculation result reveals that the resistance of the circular flue duct is only one fifth of that of rectangular flue duct, and effect of energy saving is obvious.%火力发电机组除尘器入口烟道的几何形状不仅影响除尘器入口气流的均匀性,同时也影响烟风系统的阻力大小。对空预器出口至电除尘器入口段烟道形状分别采用常规矩形烟道和圆形烟道2种设计方案。采用标准k-ε湍流模型,压力速度耦合采用SIMPLE算法。同时,利用Fluent求解器对该段烟道的流场进行数值模拟计算,对上述2种工况的烟道阻力进行分析计算。计算结果表明：圆形烟道阻力只有矩形烟道的1/5,节能效果明显。