耦合介尺度运动的液液两相搅拌流动的高精度模型和模拟

项目名称： 耦合介尺度运动的液液两相搅拌流动的高精度模型和模拟

项目编号： No.21306197

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 化学工业

项目作者： 冯鑫

作者单位： 中国科学院过程工程研究所

项目金额： 25万元

中文摘要： 放大效应是导致工业搅拌反应器产品收率低、物耗能耗高的关键问题之一。随着计算机的发展，数学模型和数值模拟逐渐成为研究反应器放大效应的有效方法。传统的多相流动模型和方法在模拟搅拌槽内液液体系流动方面精度偏低，而高精度的模拟方法又存在数值稳定性差、计算消耗大等缺点。为解决上述问题，本项目从多相流动数学模型和模拟方法出发，对搅拌槽内液液体系两相流动进行模拟研究。围绕"耦合介尺度运动的多相流动模型"这一科学问题，构建介尺度行为影响下的两相显式代数应力模型（EASM）和湍流及相含率修正的相间作用力模型，结合粒数平衡方程（PBE）形成CFD-EASM-PBE耦合模型和计算方法。为了验证模拟结果，采用粒子图像测速（PIV）方法对搅拌槽液液流动关键参数进行测量。最终形成可靠的高精度、低计算负荷的多相流动模拟工具，为优化调控液液快反应过程、降低放大效应奠定理论基础。

中文关键词： 搅拌槽；显式代数应力模型；数值模拟；多相流；微观混合模型

英文摘要： Scale-up effect is one of the key problems resulting in low production yield and high material/energy consumption of industrial stirred reactors. With development of computational technology, mathematic model and numerical simulation become gradually a reliable way to understand the scale-up effect. Traditional multiphase models have the shortcoming of low computational accuracy when simulating liquid-liquid flow in stirred tanks. Besides, high-accuracy numerical methods are encountered with poor numerical stability and huge computational load. In order to overcome these problems, multiphase flow models and numerical methods for the simulation of liquid-liquid flow in stirred tanks are investigated in this project. Based on mesoscale dynamic models, the two-phase explicit algebraic stress model (EASM) and interphase drag force model with turbulence and phase holdup corrections are to be developed. Combining with the population balance equation (PBE), a CFD-EASM-PBE coupled model and numerical method will be established. In addition, particle image velocimetry (PIV) technique is employed to measure some key parameters of liquid-liquid flow for validation of the model and numerical method developed. Thus, a reliable research tool for multiphase flow with high-accuracy and low computational cost is anticipated, whi

英文关键词： stirred tank；explicit algebraic stress model；numerical simulation；multiphase flow；micromixing model