Numerical investigation of effects of inner cone on flow field, performance and erosion rate of cyclone separators
Numerical investigation of effects of inner cone on flow field, performance and erosion rate of cyclone separators
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DOI：
10.1016/j.seppur.2018.03.001
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发表时间：
2018-08
影响因子：
8.6
通讯作者：
F. Parvaz;S. Hosseini;Khairy Elsayed;G. Ahmadi
中科院分区：
文献类型：
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作者：
F. Parvaz;S. Hosseini;Khairy Elsayed;G. Ahmadi
气体旋风分离器在分离固体和液体与气体方面有许多工业应用。旋流器的几何形状是影响其性能的最重要参数。本文研究了位于旋风分离器底部的内锥对旋风分离器性能的影响。采用雷诺应力湍流模型（RSM）对不同直径和高度的内锥气旋进行了CFD模拟。采用欧拉-拉格朗日方法研究了旋风分离器的收集效率。结果表明，最大切向速度为进口速度的1.6 ~ 1.7倍。另一方面，在穿过内锥的径向截面上，轴向和切向速度的梯度为零。最大的轴向和切向速度发生在内锥顶部到旋涡探测器之间的区域。结果表明，在一定直径条件下，增大旋流器的内锥高度可以提高旋流器的收集性能。然而，内锥直径的增加会导致旋风分离器性能的下降。总的来说，随着内锥高度和直径的增加，压力损失减小。最后，利用挪威船级社（DNV）侵蚀模型进行侵蚀研究。结果表明，恢复系数的取值对预测侵蚀速率有一定的影响。在CFD模型中加入冲蚀效应后，集尘效率下降，特别是在较高流速下。
Gas cyclones have many industrial applications for separation of solids and liquids from gases. The geometry of the cyclone is the most influential parameter for its performance. This study investigates the effect of presence of an inner cone located at the bottom of the cyclone on the performance of the cyclone separator. Several CFD simulations in cyclones with inner cones with different diameters and heights were performed using the Reynolds stress turbulence model (RSM). The collection efficiency of the cyclone was studied using the Eulerian-Lagrangian approach. The results showed that the maximum tangential velocity is 1.6–1.7 times the inlet velocity. On the other hand, in the radial sections crossing the inner cone, the gradients of the axial and tangential velocities are zero. The maximum axial and tangential velocities occurred in the region between the top of the inner cone to the vortex finder. It was found that by increasing the inner cone height at constant diameter, the cyclone collection performance improves. An increase in the diameter of the inner cone, however, leads to a decrease in the cyclone performance. In overall, with an increase in the inner cone height and diameter, the pressure loss decreases. Finally, the erosion study was conducted using the Det Norske Veritas (DNV) erosion model. It was found that the value of coefficient of restitution affects the predicted erosion rate. In addition, the collection efficiency decreases when the erosion effect was included in the CFD model especially for higher velocities.