文献类型：期刊文献

英文题名：CFD simulation of hydrocyclone-separation performance influenced by reflux device and different vortex-finder lengths

作者：Tian, Jinyi[1];Ni, Long[2,3];Song, Tao[2,3];Zhao, Jianing[2,3]

机构：[1]East China Univ Sci & Technol, Natl Engn Lab Ind Wastewater Treatment, Shanghai 200237, Peoples R China;[2]Harbin Inst Technol, Sch Architecture, Harbin 150090, Heilongjiang, Peoples R China;[3]Minist Ind & Informat Technol, Key Lab Cold Reg Urban & Rural Human Settlement E, Harbin 150090, Heilongjiang, Peoples R China

年份：2020

卷号：233

外文期刊名：SEPARATION AND PURIFICATION TECHNOLOGY

收录：;EI(收录号：20193707417838);WOS:【SCI-EXPANDED(收录号:WOS:000490044400029)】；

基金：This work was financially supported by the National Natural Science Foundation of China (51978200).

语种：英文

外文关键词：Enhanced separation; Hydrocyclone; Reflux device; Vortex-finder length; Sewage source heat pump

摘要：Hydrocyclone has a history of approximately 129 years, and its separation performance is closely related to its vortex-finder length. To date, however, most studies have been limited to the range of from 0 to cylindrical-section length, and almost all researchers argue that the optimum vortex finder is shorter than the cylindrical-section length. To comprehensively study the effect of vortex-finder length and understand its mechanism, a hydrocyclone with reflux device and vortex-finder length of from 0 to twice cylindrical-section length was studied with FLUENT. Reynolds Stress Model and Discrete Phase Model were used. Results showed that, when the vortex-finder length was not longer than the cylindrical-section length, both the separation efficiency and split ratio were proportional to the vortex-finder length in general. This was consistent with the sandy-water experimental results obtained by Ni et al. in 2017. When it was just a little longer than the cylindrical-section length, they first decreased and then increased slightly with increase of the vortex-finder length due to effect of the cylindrical-conical interface. When the vortex-finder length was long enough, the separation efficiency was always close to 100%, whereas the split ratio was inversely proportional to the vortex-finder length. Because at this time, the axial distance between two minimum-pressure positions in the centric-axial direction was inversely proportional to the vortex-finder length, and it was so small that the fluids on the two positions could attract each other. Even at the vortex-finder length of 475-535 man, they were combined into one. Consequently, some "circulation eddies" appeared near bottom of the vortex finders with length of 415-535 mm and near top of the underflow pipe at the vortex-finder length of 535 mm. Besides, the high separation efficiency (99.87-100%) and low split ratio (29.13-32.54%) were simultaneously obtained when the vortex-finder length was 1.68-2.02 of cylindrical-section length.