Simulation of Molding of Long Fiber Thermoplastic Composites

该奖项的目标是模拟含有长纤维的聚合物流体的成型，重点是预测纤维取向，纤维构型和流动过程中产生的应力。将开发新的实验流变学技术，这将使人们能够评估的理论，预测长纤维的配置和方向下定义明确的流动条件，并确定所需的数值模拟的模型参数。 从成型操作的数值模拟的纤维取向和配置的预测将与实验确定的值从成型零件进行比较。这项工作是我们以前的努力短纤维悬浮液的延伸，但需要改进流变技术的发展，延长和修改的理论，长柔性纤维配置和修改的技术测量纤维取向。 如果成功的话，这项研究的结果将导致一个更好的理解之间的关系流和纤维的配置和取向的浓缩长纤维悬浮液。 从这一理解，理论的聚合物流体含有浓缩水平的长纤维，其中应力和颗粒取向直接相关的将被修改和改进。 基于基本流动行为的输入，本研究将产生一个模拟复杂流动中长柔性纤维取向的数值方案。 来自基本流动实验的信息将被纳入模拟包建模成型操作，这将提供给各种公司（如汽车，航空航天等）。以及用于预测模具设计以获得具有最佳性能的部件的机构。研究生将学习包含高纵横比颗粒的聚合物悬浮液的建模，实验和数值模拟。本科生将被纳入研究工作，在那里他们将学习工艺设计的重要性，以提供最佳性能的零件。

The goal of this award is to simulate the molding of polymeric fluids containing long fibers with the emphasis on predicting fiber orientation, fiber configuration and stresses generated during flow. Novel experimental rheological techniques will be developed which will allow one to assess the theories for predicting long fiber configuration and orientation under well-defined flow conditions and to determine model parameters which are needed for the numerical simulations. Predictions for fiber orientation and configuration from a numerical simulation of molding operations will be compared against experimentally determined values taken from molded parts. This work is an extension of our previous effort on short fiber suspensions but requires the development of improved rheological techniques, extension and modification of theories for long flexible fiber configuration and modification of techniques for measuring fiber orientation. If successful, the results of this research will lead to an improved understanding of the relation between flow and fiber configuration and orientation for concentrated long fiber suspensions. From this understanding, theories for polymeric fluids containing concentrated levels of long fibers in which stress and particle orientation are directly related will be modified and improved. A numerical scheme for simulating the orientation of long flexible fibers in complex flows based on input from basic flow behavior will arise from this research. Information from the basic flow experiments will then be incorporated into a simulation package modeling molding operations, which will be made available to various companies (e.g. automotive, aerospace, etc.) and agencies for predicting mold design for obtaining parts with optimum performance. Graduate students will learn about the modeling, experiments, and numerical simulations of polymeric suspensions containing high aspect ratio particles. Undergraduate students will be integrated into the research efforts where they will learn the importance of process design for delivering parts with optimum performance.