进口参数对旋流器分离性能的影响

摘要

进口参数是影响水力旋流器分级性能的重要因素,研究两者之间的影响规律具有重要意义.基于计算流体力学方法,以各种进口直径和进口速度的组合为研究对象,考察了进口参数对于精确分级的影响效应.结果显示:高分级精度的实现需要组合特定的进口直径和进口速度.过大的进口直径和过快的进口速度会降低分级精度.当进口直径过大时,由于短路流的显著影响,粗颗粒底流回收效率下降严重.流场分析发现原因是溢流管区域流体流动混乱程度的增加以及压力梯度的增强.与此同时,进口速度过快会导致细颗粒受到较大的离心力,引起溢流分离效率的降低.%Inlet configuration is important parameter of hydrocyclones,which has great impact on the classification performance.The effects of inlet configuration on the precise classification were studied by computational fluid dynamics under various combinations of inlet diameter and inlet velocity.The results showed that a high sharpness of classification was achieved with specific inlet diameter and inlet velocity.The separation efficiency of the coarse particles by underflow significantly decreased when inlet had an oversize diameter owing to a stronger short-circuit flow.It is resulted from the chaotic flow and the stronger pressure gradient around the vortex finder.Meanwhile,a low separation efficiency of the fine particles by overflow was achieved when inlet velocity was high,which indicated a low sharpness caused by the overlarge centrifugal force.