溢流管之幾何結構對水旋風分離器澄清效果的影響

Effect of geometric structure of Vortex Finder on clarify the effect of a Hydrocyclone.

陳建宏(Chian-Hwung Chen)

指導教授 ： 吳容銘

淡江大學/工學院/化學工程與材料工程學系碩士班/碩士(2011年)

https://doi.org/10.6846/TKU.2011.00491

摘要

本研究採用45 mm之水旋風分離器，在不同幾何結構的溢流管情形下，分別進行實驗與模擬分析，實驗方面探討不同的進口壓力與分流比對澄清效果的影響，分析粒徑分佈與分級效率。模擬方面以多相流VOF模式與紊流LES模式，模擬空氣柱並分析其流場，並以DPM模式作粒子軌跡的追蹤，將模擬結果對照實驗結果，分析不同結構溢流管的優劣。
實驗結果顯示，在各種不同壓力下，以小直管與收縮管型式的溢流管在水旋風分離器的澄清效果較好，顯然溢流管管徑越小澄清效果越好，同溢流管中，分流比越大澄清效果越好。模擬結果顯示，溢流管徑越小產生的空氣柱較小，流場較為混亂、渦流也較多，使粒子在水旋風分離器內停滯時間較長，不易產生短路流，因而提高澄清效果。

關鍵字

水旋風分離器 ； 計算流體力學 ； 溢流管

並列摘要

This study uses to realize its effect of geometric of vortex finders in a 45 mm diameter hydrocyclone. In experiment section, we use different inlet pressures and split ratios to explore particle size distribution and clarification respectively. In simulation section, the experiment data as basis, use multiphase VOF model and LES turbulence model to simulation and analyze the air core, and use DPM model for particle trajectory tracking. The experiment and simulation result, to analysis of the vortex finder geometric of pros and cons.

The experiment result show the different inlet pressures in the hydrocyclone to the clarification is the better of the small ascending vortex finder and the shrinkage vortex finder. Obviously, the larger the split ratio, the greater the clarification effect in the same vortex finder. The simulation result show the small diameter of vortex finder has a small air core, and the flow pattern is disorder, and has more eddy currents. That make the particles stranded within a hydrocyclone and difficult to have bearing on short-circuit, and then to improve the clarification.

並列關鍵字

Hydrocyclone ； CFD ； Vortex Finder

參考文獻

陳怡任 (2009) “水旋風分離器流場測量與模擬暨新型水旋風分離器之研究”，碩士學位論文，淡江大學化學工程與材料工程學系

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