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以立式搅拌槽为基础,借助Fluent软件κ-ε湍流模型,研究了直叶涡轮和斜叶涡轮的搅拌机内部流动,分别对标准、倾斜、离底、底部十字等不同结构挡板在搅拌槽内以恒定转速200r/min旋转时的工作状态进行了数值模拟,获得了8种情况下的功率,并据此对比速度矢量图、湍流图、速度分布曲线分析功耗改变的原因。结果表明,倾斜挡板可有效减少功率消耗,且物料在挡板处不易形成死角,工业上可采用此挡板优化搅拌功耗。底部十字挡板的流场湍流强度最大,若圆柱回转区的半径为定值时,采用底部挡板可有效防止底部固体颗粒的堆积,优化搅拌效果。若在多相搅拌过程中通过改变挡板安装方式达到颗粒沉淀、较高粘度液体充分混合等目的,需采用直叶径向流叶轮,在功率输入一定的情况下可得到合适的流场。
Based on the vertical agitating tank, the flow inside the agitator of the straight-blade turbine and the inclined-blade turbine was studied by the Fluent software κ-ε turbulence model. The influences of standard, inclined, The numerical simulation was carried out in a rotating speed of 200r / min at constant speed. The power under eight conditions was obtained. Based on this, the reasons for the change of power consumption were analyzed by comparing the speed vector, turbulence and velocity profiles. The results show that the inclined baffle can effectively reduce power consumption, and the material at the baffle is not easy to form dead ends, industrial baffles can be used to optimize the mixing power. Bottom cross baffle flow turbulence intensity maximum, if the rotating radius of the column is a fixed value, the bottom baffle can be used to effectively prevent the bottom of the accumulation of solid particles to optimize the mixing effect. If multi-phase stirring process by changing the baffle installation to achieve particle precipitation, the high viscosity of the liquid mixed well for such purposes, the need to use straight-leaf radial flow impeller, the power input can be obtained under certain circumstances appropriate flow field.