旋风分离器壁面磨损数值模拟研究

CFD Study on Wall Erosion in Cyclone Separator

壁面磨损是制约旋风分离器发展的突出问题,基于计算流体力学方法研究入口速度和颗粒粒径对分离器壁面磨损及分离效率的影响。研究发现,环形空间壁面沿圆周方向的磨损速率分布规律不随入口速度变化而改变,180°至260°方位角区间磨损较严重;分离空间筒体壁面的磨损速率沿圆周方向呈现较均匀分布,锥体壁面的磨损速率随高度的减小而增大。不同单一粒径下环形空间壁面沿圆周方向磨损速率先增加后减小,且粒径较大时磨损峰值对应的方位角更小;分离空间壁面磨损速率在锥体下部达到磨损峰值,且在粒径大于30μm时会明显增加。当颗粒粒径处于8~30μm之间时,增大入口速度是提高分离器效率的有效方法;当颗粒粒径大于50μm时分离效率接近100%。

Wall erosion is a prominent problem that restricts the development of cyclone separator. Based on computational fluid dynamics, this paper investigated the influence of inlet velocity and particle size on wall erosion and separation efficiency of cyclone separator. It was found that distribution law of erosion rate in annular space did not change with different inlet velocity along circumferential direction, and the erosion was more serious in the azimuth range from 180 to 260. The erosion rate of cylinder wall in separation space was evenly distributed along the circumferential direction, and the erosion rate of cone wall increased with the decrease of height. The erosion rate of annular space wall along the circumferential direction increased at first and then decreased with different particle size,and the azimuth angle corresponding to the erosion peak was smaller when the particle size was larger;The erosion rate reached the maximum at the lowest part of cone, and increased obviously when the particle size was larger than 30μm.When the particle size was between 8μm and 30μm, increasing inlet velocity was an effective method to improve the efficiency of separator. When the particle size was larger than 50μm, the separation efficiency was nearly 100%.