GOALI: Segregation of Sheared Particle Mixtures

国家科学基金会--化学与运输系统部门？颗粒和安培；多阶段工艺计划(1415年)提案编号：0730767首席调查员：格拉斯尔，本杰明隶属关系：罗格斯大学提案标题：GOALI：剪切颗粒混合物的分离与流体处理同行相比，许多行业中的颗粒处理操作往往知之甚少。产品质量和一致性经常受到不均匀流动和成分分离等问题的威胁，后者在制药行业中尤为重要，因为在制药行业中，维持均匀的颗粒混合物至关重要。传统上，启发式经验法则被用来限制这些问题，但这些规则并没有可靠地预测和防止在扩大规模或试运行期间发生分离。从质量控制、商业或监管的角度来看，更可取的方法是能够根据基本原理、材料特性和小规模实验室测试来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一致性的不利影响。虽然颗粒流有越来越多的理论基础，但它还没有广泛应用于工业中典型的非均匀或非稳定流。智能优点：从根本上说，分离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-工业合作项目中，我们将通过数值和实验研究Couette和Taylor-Couette几何结构以及圆柱形搅拌器中发生的分离。Couette和Taylor-Couette流可能是同时包含剪切和物理边界相互作用的最简单的模型几何形状？实用流程的基本要素。虽然圆柱形搅拌器稍微复杂一些，但也包括剪切和边界相互作用；我们将研究由四个倾斜叶片搅拌的圆柱形搅拌器中的流动和分离。粒子动力学模拟技术将被用来模拟粒子的性质，所产生的流动将与运动学理论的结果进行比较。实验流动将使用粒子图像测速仪(PIV)、流采样和图像分析技术进行检查。然后将研究不稳定作为分离的触发因素的后续作用，最终计算给定颗粒物种的分离通量。计算和物理实验将被用来根据相关的无量纲群来表征混合-分离转变。对于混合或运输作业中典型的高剪切流和中剪切流，将描述由不均质性引发的颗粒分离机制。更广泛的影响：本提案中的研究倡议将与教育和推广倡议相结合，包括研究生、本科生和高中的粒子技术研究培训。粒子技术培训一直被认为是一个国家需要的领域，但在美国传统上被忽视了。作为这项提议的一部分，PI将继续推动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，该学院吸引新泽西州的高中生到罗格斯大学参加高中与大学的交流项目。最后，和平协会将继续以招募妇女和少数群体为目标。

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.