【作者】 肖建军；

【导师】 黄雄斌；

【作者基本信息】 北京化工大学 ， 化学工程， 2002， 硕士

【摘要】 搅拌功率和循环流量是考察搅拌桨性能和搅拌槽内混合效果的两个重要参数。本文在直径为0.5m和0.8m的带导流筒的搅拌槽内，采用热示踪热响应法系统考察了搅拌桨型、导流简直径和离底距离、静液位高度、列管设置及其流通面积对搅拌功率及循环流量的影响。并根据工艺要求优选出新的搅拌桨型式，新搅拌桨比现工业用桨在消耗相同功率的条件下能产生更大的循环流量。 本文利用激光多普勒测速技术，在直径为0.5m的搅拌槽中，详细的研究了导流筒对搅拌槽内流场的影响，并分析了导流筒-搅拌槽体系内结构参数变化对流场的影响情况。结果表明，导流筒-搅拌槽体系能产生更大的循环流量。 利用计算流体力学软件FLUENT-5，对带导流筒搅拌槽内的流场进行了数值模拟。将模拟结果与实验结果进行比较，发现二者基本一致。更多还原

【Abstract】 Power demand and liquid circulation flux are important for appraising performance of impeller and the effect of mixing in a stirred tank. The effects of impeller type, diameter of draft-tube, clearance between draft-tube and the bottom of tank, liquid height, tube number and circulation area on the circulation flux were systematically investigated by thermo-tracing responding system in flat bottom cylindrical draft tube vessels of 0.5 m and 0.8 m in diameter. A new type of impeller was designed to generate more liquid circulation under the same power input.In this paper, the effect of draft-tube on flow field was studied in detail by using laser-Doppler velocimetry in the vessel of 0.5 m in diameter. The effects of geometry parameters of the draft tube tank on the flow field has also been analyzed. It was found that the draft-tube could enhance liquid circulation.The commercial code of CFD (Computational Fluid Dynamics), FLUENT-5, has been used to numerically simulate the flow field in the draft-tube agitated tank. It was shown that the predicted results were in qualitative agreement with the experimental data.更多还原