基于CFD流场分析的反应釜搅拌器结构改进

Improvement of Reaction Kettle Agitator Based on CFD Analysis

承压反应釜在固液混合过程中往往伴随强烈的热传递效应,而密度较低的粉末状固相介质与液体混合的难度相对较大,投料溶入效果不佳和物料结团漂浮等问题较常见。针对此类反应釜的搅拌不充分等问题,采用CFD技术指导反应釜内搅拌器结构进行设计和改进,对反应釜内的固液搅拌混合过程进行了三维数值模拟。数值计算采用多重参考系法(MRF),κ-ε湍流模式以及Mixture多相流模型,模拟了反应釜中的流场形态,通过混合过程的两相流计算得到固相体积分数的分布情况和变化规律,并在此基础上预测了混合时间。结果表明:改进后的搅拌器效果明显增强,该混合过程的CFD模拟可得到相对准确的流场分布及各项特性参数预测结果,可为该类反应釜搅拌器的设计和优化提供参考。

The process of solid-liquid mixing in reaction kettle is often accompanied by strong heat transfer effect.Low density powder and liquid mixing process is hard to control and often with poor mixing effect.For the problems such as insufficient mixing reaction kettle,structural design,improvement of the reaction kettle agitator by using CFD technology was carried out.In the CFD simulation,multiple reference frame （MRF）,standard κ-ε turbulence model and the Mixture multiphase flow model were adopted.Through the simulation,the solid particle volume fraction distribution and mixing time of unsteady two-phase mixing process was predicted.The results show that the CFD simulation of the mixing process can obtain more accurate solid-liquid flow field distribution and the characteristic parameters.The calculation results can provide references for the design of this kind of reaction kettle agitator.