GOALI: Segregation of Sheared Particle Mixtures

美国国家科学基金会-化学运输系统司？微粒多相工艺程序（1415）提案编号：0730767主要研究者：Glasser，Benjamin附属机构： 罗格斯大学提案标题：目标：剪切颗粒混合物的分离与流体处理同行相比，各种行业中的颗粒处理操作通常知之甚少。产品质量和一致性经常受到诸如不均匀流动和组成成分分离的问题的威胁，后者在药物制造中尤其重要，其中保持均匀的颗粒混合物是至关重要的。传统上，启发式经验法则已被用来限制这些问题，但这些并没有可靠地预测和防止隔离发生在放大或调试。从质量控制、商业或监管的角度来看，一种更理想的方法是能够从基本原理、材料特性和小规模实验室测试中定量预测流动不均匀性和分离率，然后相应地设计工艺以限制对性能和产品均匀性的不利影响。虽然颗粒流的理论基础越来越多，但还没有广泛应用于工业情况下典型的非均匀或非定常流。智力优势：从根本上说，偏析源于系统相邻区域之间的速度和流动特性（如颗粒温度）的变化，优先将某种类型的颗粒驱动到特定位置。在这个大学与工业界的合作项目中，我们将数值和实验研究发生在库埃特和泰勒-库埃特几何形状和圆柱形混合器的分离。Couette和Taylor-Couette流也许是最简单的模型几何形状，包括剪切和物理边界相互作用？实际流程的基本要素。虽然有点复杂，圆柱形混合器也包括剪切和边界相互作用，我们将检查流动和分离的圆柱形混合器的几何形状搅拌四个倾斜的叶片。粒子动态模拟技术将用于模拟粒子特性，并将所得流与动力学理论的结果进行比较。实验流将使用粒子图像测速（PIV），流采样和图像分析技术进行检查。然后将研究不稳定性作为分离触发因素的后续作用，最终计算给定粒子种类的分离通量。计算和物理实验将被用来表征相关的无量纲组的混合偏析过渡。由不均匀性引发的颗粒分离机制的特点是，高和中等剪切流典型的混合或运输操作。更广泛的影响：本提案中的研究举措将与教育和推广举措相结合，包括粒子技术的研究生、本科生和高中研究培训。粒子技术的培训已被公认为国家需要的一个领域，但在美国传统上被忽视。作为这项提议的一部分，PI将继续推进粒子技术进入罗格斯大学的课程。高中生将有机会通过州长工程学院获得研究经验，该学院吸引新泽西高中生到罗格斯大学参加高中-大学交流项目。最后，PI将继续针对妇女和少数民族的招聘。

National Science Foundation - Division of Chemical &Transport Systems ? Particulate & Multiphase Processes Program (1415)Proposal Number: 0730767 Principal Investigators: Glasser, Benjamin Affiliation: Rutgers University Proposal Title: GOALI: Segregation of Sheared Particle Mixtures Particulate processing operations in a wide variety of industries are often poorly understood compared to their fluid processing counterparts. Product quality and consistency is frequently threatened by problems such as non-uniform flow and segregation of constituent components, the latter being especially significant in pharmaceutical manufacture in which maintenance of a homogenous particle mixture is critical. Traditionally, heuristic rules-of-thumb have been used to limit these problems, but these have not reliably predicted and prevented segregation from occurring during scale-up or commissioning. A more desirable approach, from either a quality control, commercial, or regulatory perspective, is the ability to quantitatively predict flow inhomogeneities and segregation rates from fundamental principles, material properties and small-scale laboratory tests, and then to engineer processes accordingly to limit detrimental effects on performance and product uniformity. While there is a growing theoretical basis for granular flow, this has not yet been applied widely to non-uniform or unsteady flows which are typical of industrial situations. Intellectual Merit: Fundamentally, segregation stems from variations in velocity and flow properties, such as granular temperature, between adjacent regions of a system, preferentially driving particles of a certain type to particular locations. In this university-industry collaborative project we will numerically and experimentally study segregation occurring in the Couette and Taylor-Couette geometries, and cylindrical mixers. Couette and Taylor-Couette flows are perhaps the simplest model geometries encompassing both shear and physical boundary interactions ? essential ingredients of practical flows. While somewhat more complex, cylindrical mixers also encompass both shear and boundary interactions; we will examine flow and segregation in a cylindrical mixer geometry agitated by four pitched blades. Particle dynamic simulation techniques will be used to model particle properties and resulting flows will be compared to results from kinetic theory. Experimental flows will be examined using Particle Image Velocimetry (PIV), stream sampling, and image analysis techniques. The subsequent role of instabilities as triggers for segregation will then be investigated, culminating in calculations of segregation flux for a given particle species. Computational and physical experiments will be used to characterize mixing-segregation transitions in terms of relevant dimensionless groups. Mechanisms of particle segregation triggered by the inhomogeneities will be characterized, for high- and intermediate-shear flows typical of mixing or transport operations. Broader Impacts: The research initiatives in this proposal will be integrated with educational and outreach initiatives including graduate, undergraduate and high school research training in particle technology. Training in particle technology has been recognized as an area of national need but has traditionally been neglected in the US. As part of this proposal, the PI will continue to advance particle technology into the curriculum at Rutgers. High school students will be given the opportunity for research experience through the Governor's School of Engineering, which attracts New Jersey high school students to Rutgers for a high school-university exchange program. Finally, the PI will continue to target the recruitment of women and minorities.