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

0932978 Olsen通过经济的、可规模化的方法从疏水性有机化合物生产均匀尺寸的纳米颗粒是非常具有挑战性的。生产精确控制尺寸的功能性纳米颗粒的最先进工艺之一是快速纳米沉淀，它需要非常快速地混合两种或更多种流以产生均匀的过饱和。目前，Flash NanoPrecipitation仅在小型生产运行的微型反应器中得到证明。这种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，如用于杀虫剂和化妆品的纳米颗粒的制造，将需要更大的生产运行，使微型反应器在经济上不切实际。出于这个原因，流体动力学和标量传输过程与规模的Flash NanoPrecipitation能够产生大量的功能性纳米粒子的宏观反应器将在本研究项目中使用相结合的实验和建模方法进行研究。对快速沉淀的基本理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，以及Flash NanoPrecipitation（例如毫秒微观混合）所需的处理条件的可扩展性是一个悬而未决的问题，将在这里解决。为了回答这个问题，湍流反应混合在宏观多入口涡流混合器（MIVM）反应器将使用非侵入式光学测量技术进行研究，从这些实验的结果将被用来开发和验证计算流体动力学（CFD）模型的混合和反应过程。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），并同时PIV/PLIF。计算流体动力学模型将基于大涡模拟（LES）和采用直接矩量积分法（DQM）求解的传输概率密度函数（PDF）模型。一旦开发和验证，这些CFD模型可以被化学加工行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性纳米颗粒。智力优势：湍流反应流的计算模型的发展，特别是在复杂的旋流几何形状，如在涡流反应器中，是一个重要的技术和智力挑战。例如，在湍流反应流的CFD模型中，化学源项的亚网格尺度闭合对于复杂的液相反应流没有得到充分的验证，这是由于在定义明确的反应器几何形状中缺乏局部速度和浓度场的详细实验数据。更广泛的影响：Flash NanoPrecipitation显示出生产有机化合物的均匀尺寸的功能性纳米颗粒的前景。然而，该方法仅在仅能够产生非常小的生产运行的微型反应器中得到证实。将快速纳米沉淀工艺放大到大规模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掌握最先进的工程工具，用于扩大和设计化学反应器。

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.