全挡板条件下挡板数目对搅拌式反应罐内部流场的影响

Influence of different numbers of baffles on the flow field in a stirred tank under full-baffle condition

采用多相流模型和滑移网格法,应用CFD软件,研究了在全挡板条件下不同数目挡板的搅拌式反应罐内部的流体动力学特性。为研究挡板数目对搅拌式反应罐内物料流动规律的影响,文中对搅拌桨旋转40周时的数值模拟结果进行了比较,分析了不安装挡板、安装4块挡板和安装6块符合全挡板条件挡板的搅拌式反应罐在内部流场、流速、气液两相的分布状态以及搅拌轴输出扭矩等方面的差异,模拟结果表明,挡板能有效消除罐内流体漩涡、增强湍动作用、加强罐内物料的搅拌混合特性;安装4块符合全挡板条件的挡板能很好地满足各方面要求。

This paper studies the fluid dynamics characteristic in the stirred tank with different number of baffles in the full-baffle condition , by using general multiphase model , sliding mesh method , and the CFD software .In order to study the effects of different numbers of baffles on the flowing law of the internal materials , the numerical simula-tion results after 40 rotations of stirring blades are compared , and the differences in the internal flow field , flow ve-locity, distribution of gas-liquid phases as well as torque output of stirring shaft , in non-baffle stirred tank and stirred tanks with four and six baffles in full-baffle condition , are summarized .The conclusions are drawn as fol-lows：baffles can effectively eliminate vortex , enhance turbulent effects and mixing characteristics of internal mate-rials.And four baffles under full-baffle condition can best meet all requirements .