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本文用照相法测定了锚式搅拌槽中高粘度流体的流型和速度分布.利用最小二乘法获得速度分布拟合方程以及槽中剪切率γ和耗散能Φ分布方程.比较了槽壁区域剪切率和全槽平均剪切率、Metzner常数k_S和搅拌器特性参数C_3,指出k_S是表征槽中高剪切区域剪切率大小的特征量,C_3表征了全槽平均剪切率的大小.对于均匀剪切场,两者是一致的.可以用单位体积剪切率分布系数φ_V来描述槽中剪切率分布的均匀程度.本文还研究了Re数对速度分布流型的影响,发现在低Re数下,流型是对称的.高Re数下,流型则不对称.
In this paper, the flow pattern and velocity distribution of high-viscosity fluid in an anchor-type stirred tank were measured by photographic method, the fitting equation of velocity distribution and the distribution of shear rate γ and dissipation energy Φ in the tank were obtained by the least squares method, Shear rate and the average shear rate of the whole tank, the Metzner constant k_S and the stirrer characteristic parameter C_3. It is pointed out that k_S is the characteristic quantity that characterizes the shear rate of the high shear zone in the tank, and C_3 indicates the average shear rate of the full tank. For the uniform shear field, the two are consistent, and the uniform distribution of the shear rate in the slot can be described by the distribution coefficient φ_V of the unit shear rate.We also study the influence of the Re number on the velocity distribution pattern, Under the low Re number, the flow pattern is symmetrical, and under the high Re number, the flow pattern is not symmetrical.