Influence of new outlet configurations with baffle on hydrocycloneon separation performance

doi:10.11949/j.issn.0438-1157.20171066

Abstract

Abstract:

The influence of new outlet configurations, which are designed with different internal baffles in the vortex finder and the underflow pipe, on the separation performance is investigated experimentally in a small hydrocyclone with a diameter of 50 mm. It is indicated that the vortex finder with internal baffles is suitable for the working conditions of a high throughput. Compared with that of traditional vortex finders, the separation efficiency of vortex finders with internal baffles in the hydrocyclone decreased slightly, but the pressure drop reduced remarkably to 11.11% at high flow rates. Three pieces of narrow and short baffles, which are spaced at regular intervals around the inner wall of the vortex finder, are recommended. It is found that the cross-shaped internal baffles in the underflow pipe can stabilize the inner vortex flow therein, and the separation efficiency can be improved by 5.96%. If the vortex finder and the underflow pipe are designed with the optimized baffles, the separation efficiency can be enhanced and meanwhile the pressure drop can be decreased. In addition, it is observed that the vortex finder with the internal baffles can eliminate the air core inside the hydrocyclone. It is inferred that the air core is not produced by air, but it is a forced swirl vortex with a high turbulence formed in the central zone with a negative gauge pressure.

Key words: separation, experimental validation, flow, hydrocyclone, vortex finder, underflow pipe, air core

摘要：

针对小直径水力旋流器，设计了不同内置挡板式的溢流管和底流管，实验研究了新型出口挡板结构对水力旋流器分离性能的影响。研究结果表明：内置挡板溢流管适用于处理量较大的工况，与传统溢流管相比，分离效率略有降低，但在高流量下其压降的降低幅度可达11.11%，挡板宜采用相对较窄、较短、三块120°间隔设计方式；底流管内置挡板采用十字交叉结构可稳定内旋流，使分离效率最大可提高5.96%；新型内置挡板的溢流口与底流口相耦合，可同时实现提高分离效率和降低压降的目标。此外，在相同情况下，发现溢流管内置挡板可消除水力旋流器内部的“空气柱”，据此推断“空气柱”并非由内部空气形成，而是其内部负压中心形成的某种湍流程度较高的强制旋流涡。

关键词: 分离, 实验验证, 流动, 水力旋流器, 溢流管, 底流管, 空气柱

CLC Number:

TQ028.54

LIU Hongyan, HAN Tianlong, WANG Ya, HUANG Qingshan. Influence of new outlet configurations with baffle on hydrocycloneon separation performance[J]. CIESC Journal, 2018, 69(5): 2081-2088.

刘鸿雁, 韩天龙, 王亚, 黄青山. 水力旋流器新型出口挡板结构对分离性能的影响[J]. 化工学报, 2018, 69(5): 2081-2088.

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