To solve the long-term restrictions on the development of hydrocyclones (i.e., underflow diameter is difficult to flexibly and stably control, and underflow orifice and pipe are easy to be blocked), in 2017, researchers enhanced the hydrocyclone separation by using the underflow pumping to adjust the back pressure ratio, namely, ratio of the absolute underflow pressure to absolute overflow pressure. However, the effect of back pressure ratio may be affected by overflow pressure, whereas the pressure drop ratio, i.e., ratio of overflow pressure drop (pressure difference between inlet and vortex-finder outlet) to underflow pressure drop (pressure difference between inlet and underflow orifice), may be more reliable for monitoring the hydrocyclone-separation performance. Therefore, in this study, Discrete Phase Model and low-Re stress-omega Reynolds Stress Model, with which the near-wall sub-layer can be resolved, were employed to numerically and comprehensively compare their effects on the hydrocyclone-separation performance. Results indicate that, compared with back pressure ratio, pressure drop ratio is a more reliable parameter monitoring the hydrocyclone-separation performance. The reason is that, unlike the back pressure ratio, the effect of pressure drop ratio is basically not affected by the increase of overflow pressure. The optimum pressure drop ratio of the simulated hydrocyclone is within 119.3%-135.3%. Because only at this time, the high separation efficiency (86.25%-98.96%), small split ratio (0-16.07%), and the low total static pressure loss (2569.83-2951.58 Pa) can be simultaneously obtained. With increase of the pressure drop ratio, the split ratio linearly decreases, whereas the total static pressure drop decreases slower in general. This is consistent with the experimental results obtained by other researchers. The pressure drop ratio is proportional to the self-rotation speed of inertia-free particles in upper part of the hydrocyclone, whereas is inversely proportional to that in lower part of the hydrocyclone, especially that near the apex.

为了解决对旋流器发展的长期限制（即底流直径难以灵活，稳定地控制，底流孔和管道易于堵塞），2017年，研究人员通过使用底流抽水技术增强了水力旋流器的分离调整背压比，即绝对下溢压力与绝对上溢压力的比率。但是，背压比的影响可能受溢流压力的影响，而压降比，即溢流压降（入口与涡流发现器之间的压差）与底流压降（入口与底流之间的压差）之比孔），对于监控水力旋流器的分离性能可能更为可靠。因此，在这项研究中 利用离散相模型和低Re应力-欧米诺雷诺斯应力模型，可以解析近壁子层，数值和全面地比较它们对水力旋流器分离性能的影响。结果表明，与背压比相比，压降比是监测水力旋流器分离性能的更可靠参数。原因是，与背压比不同，压降比的作用基本上不受溢流压力增加的影响。模拟水力旋流器的最佳压降率在119.3％-135.3％之内。因为仅在这时，才能同时获得高分离效率（86.25％-98.96％），小的分流比（0-16.07％）和低的总静压损失（2569.83-2951.58 Pa）。随着压降比的增加，分流比线性减小，而总静压降通常降低得较慢。这与其他研究人员获得的实验结果一致。在水力旋流器的上部，压降比与无惯性粒子的自转速度成正比，而与水力旋流器的下部，特别是在顶点附近成反比。