动叶可调轴流风机叶片磨损的仿真研究

Simulation of Blade Erosion of Variable-pitch Axial Flow Fan

受除尘系统效果影响,引风机叶片在不同颗粒粒径及颗粒质量浓度下的磨损形态和磨损率存在较大差异。利用FLUENT软件对某动叶可调轴流引风机的叶片磨损状况进行了全三维模拟,分析了轴流风机中不同粒径颗粒的运动轨迹,叶片压力面和吸力面的磨损形态及颗粒质量浓度分布,比较了不同颗粒质量浓度下叶片磨损率。结果表明:粒径主要影响轴流风机叶片磨损形态,与离心风机不同,动叶区颗粒碰撞大多发生在叶片压力面,且随粒径增大,碰撞点向前缘集中,造成叶片磨损更不均匀;颗粒质量浓度主要影响叶片磨损率,且随颗粒质量浓度增大磨损率近似呈线性变化,而对叶片磨损形态影响较小。

Affected by the performance of dust precipitators, significant differences of blade erosion regimes and erosion rates in induced draft fans are exhibited due to various particle diameters and concentrations. A 3D numerical simulation on a single-stage axial fan is carried out using Fluent to investigate the blade erosion regimes. The important features including particle trajectories under different particle diameters, erosion pattern and particle mass concentration distribution on the pressure and suction surfaces are examined, and the effect of particle mass concentration on erosion rate is analyzed. The results show that the erosion regimes are mainly affected by particle diameter. Differing from a centrifugal fan, most collisions of particles are occurred on the pressure surface, and as particle diameter increases, collision points gradually center on blade leading edge, resulting in severely inhomogeneous erosion. In addition, blade erosion rate is primarily dominated by particle mass concentration, while erosion pattern is negligibly influenced, the erosion rate deteriorates linearly with increasing particle mass concentration.