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| LES analyses of flow fields and structure improvements of hydrocyclones |
| Guo Xueyan, Wang Binjie, Yang Fan |
| School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093 |
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Abstract LES(large eddy simulation)analysis has been carried out to investigate the flow fields in a hydrocyclone. Detailed flow structures and phenomena such as shortcut flow, internal circulations, locus of zero vertical velocity(LZVV)and locus of maximum tangential velocity(LMTV), have been analyzed. Combined with theories of hydrocyclone design and fluid mechanics, modification of the internal structures was conducted, including increasing thickness of overflow pipe wall,increasing depth of overflow tube insertion, appropriately increasing length of the hydrocyclone cylinder, decreasing taper angle etc. The further LES analysis shows that thicker overflow pipe wall can effectively restrain the circulation flow near the overflow pipe; but deeper overflow tube does not obviously hamper the short-circuit flow. Longer overflow tube with appropriate cone angle can determine a better LZVV and LMTV. Compared with the original cyclone, the flow fields in the modified one are obviously improved, which implies that a better liquid-solid separation can be expected.
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Received: 22 October 2012
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