旋流器底流口直径及入料性质对固体颗粒运动的影响研究

A study of the effect of apex diameter of hydrocyclone and physical properties of feed material on motion of solid particles

结合水力旋流器分级原理,利用计算流体力学的原理和方法,在底流口直径和入料性质参数多个水平下,对旋流器内部流场进行了数值模拟,揭示了两因素对旋流器分级的影响。结果表明:增大底流口直径,流场内流速降低,零速包络面向内向上收缩,分级粒度变小;增大入料固体颗粒密度、粒度或者质量浓度,固体颗粒指向中心的径向速度减小,底流产率增加,细颗粒含量增加。根据选煤厂的实际生产工况,合理设计旋流器的结构参数,对控制分离粒度、提高分级效率尤为重要。

In line with the principle on which classification is affected in cyclone, and by applying the computational fluid mechanical principle and method, numerical simulation of the flow field inside the cy- clone is made at varying cyclone apex diameters and properties of feed material. Through the simulation, the effect of the above-going 2 factors on classification performance of the cyclone has been brought to light as evidenced by the following findings： with the increase of apex diameter, the flow velocity decrea- ses, and the zero-velocity envelope tends to shrink both inwardly and upwardly, causing eventually the diminution of classification size ; and, with the increase of density or size or mass concentration of feed, there can be seen a drop of the radial velocity of solid particles toward the center, along with a higher yield of coarser particles and higher content of finer size material in underflow. Therefore, to have the structural parameters of a hydrocyclone rationally designed according to specific operating conditions on site is of vital importance especially for the control of classification size and improvement of classification performance.