用CFD技术研究了最大叶片式桨和三层六直叶涡轮桨的在大高径比工业规模搅拌釜中流体力学行为，以黄原胶溶液为研究体系，重点考察了功率特性、死区分率、剪切性能和混合时间等流体动力学性能。结果表明：2种搅拌桨的功耗与转速成正比，死区与转速成反比；随着雷诺数增加，釜内平均剪切速率增加。工业规模搅拌釜中，最大叶片式桨搅拌流场呈双循环流型，三层六直叶涡轮桨在每个桨叶叶端分别形成上下2个小循环。在相同单位体积功耗下，最大叶片式桨的混合时间相对于三层六直叶涡轮桨较短。%By using computational fluid dynamics(CFD), the mixing characteristics of maxblend (MB) impeller and three layers of six straight blade turbine ( TT) impeller are studied in industrial scale stirred tank with high rati-o of height to diameter. Taking Xanthan gum as research system, the hydrodynamics characterizations of power characteristics, dead zone fraction, shear property and mixing time are investigated. The results show that, the pow-er consumption is directly proportional to rotational speed, dead zone fraction is inversely proportional to rotational speed, and the average shearing rate of the tank increases with the Reynolds number. In the industrial scale tank, the mixing flow field of MB impeller performs“ two-cycle” flow type, TT impeller performs two small circulations in upper and lower part of each paddle. Under the same power consumption, the mixing time of MB impeller is shorter than that of TT impeller.
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