Spatial and Temporal Behavior of the Density Field in Flowing Cohesive Powders

美国国家科学基金会-化学与运输系统分部-颗粒与多相过程项目（1415）摘要申请编号：0553819主要研究者：Tomassone， silvina隶属机构：Rutgers University New brunswick流动粘性粉末中密度场的时空行为本提案侧重于实验和计算方法的发展，以增强对催化剂，食品和制药制造中使用的粘性粉末的密度行为的理解，作为流动参数和材料特性的函数。该提案的总体目标是开发一种结合实验和数值模拟的预测方法来表征粘性材料，重点是对密度函数和膨胀效应的理解。基于x射线微计算机断层扫描（CT）的使用，将实施一种量化颗粒状材料密度波动的通用实验方法。计算方法，基于离散元方法，预测颗粒密度将获得主要用于催化剂制造的材料（二氧化硅和氧化铝）和食品和制药产品（微晶纤维素和乳糖）的粉末加工中使用的三种类型的流动：翻滚搅拌机，高剪切搅拌机和振动振动筛。智力优势：对于颗粒流动现象，尚不存在可与流体现象相媲美的统一理论。尽管非粘性粉末已经取得了重大进展，但粘性粉末领域的研究仍然相对较少。该项目将开发实验和计算工具来表征粘性粉末中密度场的行为，并揭示剪切，应力和密度的耦合相互作用，这是获得粘性颗粒材料本构关系所需的重要步骤。更广泛的影响：通过促进对这些行业重要材料密度的更好理解，拟议的研究计划将对催化剂，制药和食品行业产生直接影响。从这项工作中获得的方法可以扩展到检查许多粉末流的密度。这项工作的教育影响将通过最佳地利用现有的教育基础设施，包括制药工程的IGERT来最大化。

National Science Foundation - Division of Chemical &Transport Systems Particulate & Multiphase Processes Program (1415)ABSTRACTProposal Number: 0553819Principal Investigator: Tomassone, SilvinaAffiliation: Rutgers University New BrunswickProposal Title: Spatial and Temporal Behavior of the Density Field in Flowing Cohesive PowdersThis proposal focuses on the development of experimental and computational methods for achieving enhanced understanding of the behavior of the density of cohesive powders used in catalyst, food, and pharmaceutical manufacturing, as a function of the flow parameters and material properties. The overall goal of the proposal is to develop a predictive methodology that combines experiments and numerical simulations to characterize cohesive materials, focusing on the understanding of density functions and dilation effects. A general experimental method for quantifying density fluctuations in granular materials, based on the use of X-Ray micro computerized tomography (CT) will be implemented. Computational approaches, based on the Discrete Element Method, for predicting granular density will be obtained using materials primarily used in catalyst manufacturing (Silica and Alumina) and in food and pharmaceutical products (microcrystalline cellulose and lactose) for three types of flows used in powder processing: tumbling blenders, high shear blenders, and vibratory shakers.Intellectual Merit: A unifying theory for granular flow phenomena comparable to the one for fluids does not yet exist. Though significant progress has been made for non-cohesive powders, the field of cohesive powders remains relatively uninvestigated. This project will develop experimental and computational tools to characterize the behavior of the density field in cohesive powders, and to unravel the coupled interactions of shear, stress, and density, which is an important step required to obtain constitutive relations for cohesive granular materials.Broader Impact: The proposed research program will have direct impact on the catalyst, pharmaceutical and food industries, by promoting a better understanding of the density of materials important to these industries. Methods obtained from this work can be expanded to examine density in many powder flows. The educational impact of the work will be maximized by making optimum use of existing educational infrastructure, including an IGERT in Pharmaceutical Engineering.