基于文丘里管的非互溶性多组分液体乳化机理研究

This project studies the emulsification mechanism of non-intermiscibility multicomponent liquid based on the principle of venturi tube. A combination of theoretical and experimental, laboratory-based research methods are used to analysis the emulsification system including the venturi tube and accessory throttle. Firstly, according to the previous relevant research on gas-liquid mixture in the venturi tube, the emulsification model is set up to research the influence of the geometrical parameter of venturi tube (diffusion angle, throat diameter, length-diameter ratio and so on), the phase liquid velocity and the embed mode on the emulsification effect. Meanwhile the initial experiment can be done. Secondly, the theory model is corrected via comparative analyses between the calculated and experimental result of the emulsion uniormity, concentration field, pressure field, velocity field, turbulent kinetic energy and the turbulent dissipation rate. Based on these analysis, the inner mechanism is obtained to research the influence of the throttles such as wind turbolator model in the downstream of the venturi tube on the emulsification effect. And the simulation results are validated by test results. Finally, physical mathematics model of the integrated system including venturi tube and throttles is established, and it will not only accurately describe the physical phenomenon in the liquid mixture process, but also apply essential data to design the continuous preparation emulsion system. This project has great academic significance and application value on the optimization design of integrated system with venturi tube and the mixing process of multiphase liquid.

本项目以基于文丘里管的非互溶性多组分液体的乳化机理为研究对象。采用理论与实验相结合、以实验为主的研究方法分析文丘里管及附属节流件集成系统配制乳化液的乳化过程。首先结合前人有关文丘里管内气液混合的研究结果，建立包括文丘里管的扩散角、喉管段直径及长径比等几何参数和各相液体的速度及引入方式对乳化过程影响机理的模型并进行初步实验，将文丘里管内多组分液体的混合工况和乳化液均匀性与浓度场、压力场、速度场、湍动能和湍流耗散率等计算结果相对应以修正理论模型。在此基础上，分析文丘里管下游配套风车型扰流子等节流件改善乳化过程的内在机理并进行实验验证。最终建立含文丘里管及扰流子集成系统的非互溶性多组分液体混合的物理数学模型，准确描述液体混合过程中所涉及的若干物理现象，为乳化液体连续配制系统的设计提供基础数据，对基于文丘里管的非互溶性多组分液体乳化集成系统的优化以及多相流体的混合均具有重要的学术意义和应用价值。

研究文丘里混合器内非互溶性多组分液体的混合过程，采用理论与实验相结合、以实验为主的研究方法。通过FLUENT软件模拟分析确定文丘里混合器的结构参数，利用响应面法和数值模拟优化长径比、收缩角、扩散角和喉部直径等混合器结构参数，搭建了文丘里混合器的气水混合实验台。实验采用高速摄影仪拍摄文丘里混合器内气水掺混情况，引入了贯穿距离和喷射折角来描述气水掺混效果，基于Matlab图像处理方法捕捉气水掺混图片的气泡粒径，建立了空气压力、水压力、结构参数和引入方式等对气液掺混效果和气泡粒径分布的影响模型。另外，对文丘里混合器喉部引入孔处的气泡脱离现象进行了详细的实验和理论研究，分析了引入孔处气泡生长的动力学规律，建立了横流液体中孔口气泡生长的球状模型。基于文丘里混合器结构的优化设计，提出了多种新型文丘里混合器结构。通过对实验结果的分析，可以准确描述文丘里混合器内的气水混合过程，定性和定量的分析了若干因素对气水混合掺混效果的影响，在此基础上，对比分析了传统文丘里混合器和含插入管的文丘里混合器中油水混合流动情况，分析了混合比例对相分布的影响，为乳化液体连续配制系统的设计和优化提供基础数据，对基于文丘里混合器的非互溶性多组分液体乳化混合的研究具有重要的学术意义。