UNS: Dynamics and Rheology of Concentrated Suspensions of Rigid Rods: Effects of Confinement

CBET -1511787 PI：Jason Butler纤维通常被添加到材料中，以提供额外的强度并提高使用寿命。 然而，将纤维添加到材料中会使加工复杂化，因为纤维会导致材料在流动过程中的物理性质发生变化。 本计画将进行刚性杆悬浮于黏性液体中之流动行为之实验与电脑模拟。 该项目将研究集中悬浮液中的棒相互作用，在流动过程中。 此外，该项目将重点关注附近的围墙对悬架结构和物理性能的影响。 该项目的结果将提供信息，工程师谁处理纤维材料可以在工艺设计中使用，以提高材料性能。 该项目将为研究生提供研究培训，为感兴趣的本科生提供参与研究的机会，并通过佛罗里达大学的既定倡议加强国际合作。将在一系列设备中对浓缩纤维悬浮液的流变学进行实验研究。 为了检查约束的效果，将改变装置中的边界壁之间的距离。 附近的墙壁上的悬浮液的微观结构的影响将被确定通过成像棒。 由于限制而引起的微观结构的变化将与流体流变学的变化相关。 实验测量将与周期性边界条件或边界墙的模拟进行比较，以检查微观结构，限制和流变学之间的连接。 除了澄清约束的影响外，该项目还将确定控制浓缩悬浮棒的结构和动力学的物理机制。

CBET - 1511787PI: Jason ButlerFibers often are added to materials to provide extra strength and improve lifetime. However, adding fibers to a material complicates processing, because the fibers cause changes in the physical properties of the material during flow. This project will conduct experiments and computer simulations of the flow behavior of suspensions of rigid rods in a viscous liquid. The project will examine concentrated suspensions where the rods interact with each other during flow. Furthermore, the project will focus on the effects of nearby bounding walls on the structure and physical properties of the suspension. Results of the project will provide information that engineers who process fibrous materials can use in process design to enhance material properties. The project will provide research training for graduate students, research involvement for interested undergraduates, and opportunities to enhance international collaborations through established initiatives at the University of Florida.The rheology of concentrated fiber suspensions will be studied experimentally in a series of devices. To examine effects of confinement, the distance between bounding walls in the devices will be varied. The effects of nearby walls on the microstructure of the suspension will be determined by imaging the rods. Changes in the microstructure due to confinement will be correlated with changes in fluid rheology. Experimental measurements will be compared to simulations with periodic boundary condition or with bounding walls to examine connections between microstructure, confinement, and rheology. In addition to clarifying the influence of confinement, the project will identify the physical mechanisms that control structure and dynamics of concentrated suspensions of rods.