Influence of new outlet configurations with baffle on hydrocyclone separation performance
(2.Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong, China 266101)
(3.Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China 100190)
【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.
【Keywords】 separation; experimental validation; flow; hydrocyclone; vortex finder; underflow pipe; air core;
(Translated by HU S S)
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