Nanoprecipitation in Turbulent Liquid-Phase Vortex Reactors: A Fundamental Investigation of Scale Up Using Experimentally Validated CFD Models

湍流液相涡旋反应器中的纳米沉淀：使用经过实验验证的 CFD 模型进行放大的基础研究

• 批准号: 0932978
• 负责人: Michael Olsen
• 金额: $ 31.95万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-15 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0932978&HistoricalAwards=false
• 关键词: Nanoprecipitation; Turbulent; Liquid; Phase; Vortex

0932978OlsenThe production of uniform-sized nanoparticles from hydrophobic organic compounds by an economical, scalable process is very challenging. One of the most advanced processes to produce functional nanoparticles of precisely controlled size is Flash NanoPrecipitation, which requires very fast mixing of two or more streams to create uniform supersaturation. Presently, Flash NanoPrecipitation has only been demonstrated in microscale reactors with small production runs. This limitation is only suitable for selected applications, such as the production of high-value pharmaceutical agents. Other applications, such as the manufacturing of nanoparticles used in pesticides and cosmetics, will require much larger production runs, making microscale reactors economically unrealistic. For this reason the fluid dynamics and scalar transport processes associated with scale up Flash NanoPrecipitation to macroscale reactors capable of generating large quantities of functional nanoparticles will be investigated using a combined experimental and modeling approach in this research project. A fundamental understanding of rapid precipitation requires a detailed knowledge of the roles of macro, meso- and micromixing on the development of supersaturation, and the scalability of the processing conditions needed for Flash NanoPrecipitation (e.g. millisecond micromixing) is an open question that will be addressed here. To answer this question, turbulent reactive mixing in a macroscale multi-inlet vortex mixer (MIVM) reactor will be studied using non-intrusive optically based measurement techniques, and the results from these experiments will be used to develop and validate computational fluid dynamics (CFD) models of the mixing and reaction processes. The experimental techniques will include time-correlated (high-speed) stereo particle image velocimetry (SPIV), passive scalar and reactive planar laser induced fluorescence (PLIF), and simultaneous PIV/PLIF. The CFD models will be based on large eddy simulations (LES) and transported probability density function (PDF) models solved using the direct quadrature method of moments (DQMOM). Once developed and validated, these CFD models can be used by the chemical process industry as engineering tools for optimizing reactor design and operating parameters to produce customized functional nanoparticles in plant-scale MIVM reactors. Intellectual Merit: The development of computational models of turbulent reacting flows, especially in complex swirling geometries such as in a vortex reactor, is an important technical and intellectual challenge. For example, none of the subgrid scale closures for the chemical source term in CFD models of turbulent reacting flows have been fully validated for complex liquid-phase reacting flows due to a lack of detailed experimental data for the local velocity and concentration fields in well-defined reactor geometries. Broader Impact: Flash NanoPrecipitation shows promise for producing uniform-sized functional nanoparticles of organic compounds. However, this process has only been demonstrated in microscale reactors capable of producing only very small production runs. Scaling up the Flash NanoPrecipitation process to a macroscale MIVM reactor could greatly increase the commercial viability of this process for manufacturing a wider range of valuable end products. This project will also train students in state-of-the art engineering tools for scale up and design of chemical reactors.

0932978Olsen通过经济、可扩展的工艺从疏水性有机化合物生产均匀尺寸的纳米颗粒非常具有挑战性。生产尺寸精确控制的功能纳米颗粒的最先进工艺之一是闪速纳米沉淀，它需要非常快速地混合两个或多个流以产生均匀的过饱和度。目前，闪速纳米沉淀仅在小规模生产的微型反应器中得到验证。此限制仅适用于选定的应用，例如高价值药剂的生产。其他应用，例如用于农药和化妆品的纳米粒子的制造，将需要更大规模的生产运行，使得微型反应器在经济上不切实际。因此，本研究项目将使用实验和建模相结合的方法，研究与将 Flash NanoPrecipitation 扩大到能够生成大量功能纳米粒子的宏观反应器相关的流体动力学和标量传输过程。对快速沉淀的基本了解需要详细了解宏观、介观和微观混合对过饱和发展的作用，并且闪存纳米沉淀（例如毫秒微混合）所需的处理条件的可扩展性是一个有待解决的悬而未决的问题这里。为了回答这个问题，将使用非侵入式光学测量技术来研究宏观多入口涡流混合器 (MIVM) 反应器中的湍流反应混合，这些实验的结果将用于开发和验证计算流体动力学 (CFD) ）混合和反应过程的模型。实验技术将包括时间相关（高速）立体粒子图像测速（SPIV）、被动标量和反应平面激光诱导荧光（PLIF）以及同时PIV/PLIF。 CFD 模型将基于大涡模拟 (LES) 和使用矩直接求积法 (DQMOM) 求解的传递概率密度函数 (PDF) 模型。一旦开发和验证，这些 CFD 模型可以被化学加工工业用作优化反应器设计和操作参数的工程工具，以在工厂规模的 MIVM 反应器中生产定制的功能纳米颗粒。智力优点：湍流反应流计算模型的开发，特别是在复杂的旋转几何形状（例如涡流反应器）中，是一项重要的技术和智力挑战。例如，由于缺乏井中局部速度和浓度场的详细实验数据，湍流反应流 CFD 模型中化学源项的亚网格尺度闭合尚未针对复杂的液相反应流进行充分验证。定义的反应器几何形状。更广泛的影响：Flash NanoPrecipitation 显示出生产尺寸均匀的有机化合物功能纳米颗粒的前景。然而，这一过程仅在只能生产非常小批量生产的微型反应器中得到证实。将闪速纳米沉淀工艺扩展到大规模 MIVM 反应器可以大大提高该工艺的商业可行性，以制造更广泛的有价值的最终产品。该项目还将培训学生使用最先进的工程工具来扩大和设计化学反应器。