SBIR Phase I: Software for Three-Dimensional Simulation of Polymer Coextrusion

这个小企业创新研究（SBIR）的第一阶段项目包括开发用于精确模拟聚合物共挤出的软件。尽管使用共挤出软件对优化工艺至关重要，但塑料行业的模具设计师很少使用商业共挤出软件，因为这些软件包无法模拟复杂的共挤出系统，而且它们也无法捕捉聚合物流变学的各种复杂性。提出的共挤出软件将使用独特的专有本构理论，可以准确地捕捉聚合物的复杂流变行为。共挤压系统中四面体有限元的三维网格在共挤压模拟过程中保持不变。不再要求不同聚合物之间的界面与有限元边界相匹配，而是允许界面穿过有限元。新软件中的这些创新功能将允许模拟复杂的共挤压系统。新软件将消除目前用于设计共挤出系统的试错方法，并将共挤出产品的上市时间缩短50%以上。尽管在共挤压实验中已经观察到高黏度聚合物被低黏度聚合物包封、聚合物界面不稳定等复杂现象，但这些现象背后的机制仍未完全了解。该软件将在该项目中开发，将加强对聚合物共挤出过程中遇到的各种复杂性背后的根本原因的科学理解。它将为设计工程师和工程学生提供一个有用的工具来进行优化共挤压系统的数值实验。许多不同类型的公司，包括塑料材料供应商、塑料零件制造商和挤出设备制造商，将能够使用该软件降低成本并增加收入。计划在密歇根理工大学和马萨诸塞大学进行的共挤压模拟实验验证将有利于工程教育。在这个项目中发展的科学知识将被纳入密歇根理工大学的高级课程。

This Small Business Innovative Research (SBIR) Phase I project involves development of software for accurate simulation of polymer coextrusion. Even though use of coextrusion software is critical for optimizing the process, die designers in the plastic industry rarely use commercial coextrusion software because these packages cannot simulate complex coextrusion systems, and they also fail to capture various complexities of polymer rheology. The proposed coextrusion software will use a unique proprietary constitutive theory, which can accurately capture the complex rheological behavior of polymers. The three-dimensional mesh of tetrahedral finite elements in the coextrusion system will remain unaltered during the coextrusion simulation. Instead of requiring the interface between different polymers to match with finite element boundaries, the interface will be allowed to cut through the finite elements. These innovative features in the new software will allow simulation of complex coextrusion systems. The new software will eliminate the trial-and-error approach currently being used to design coextrusion systems, and it will cut the time to market of coextruded products by over 50 percent.Even though complex phenomena, such as encapsulation of high viscosity polymer by less viscous polymer, and instabilities at polymer interface, have been observed in coextrusion experiments, the mechanisms behind these phenomena are still not understood completely. The software, which will be developed in this project, will enhance the scientific understanding of the root cause behind various complexities encountered in polymer coextrusion. It will provide design engineers as well as engineering students a useful tool to perform numerical experiments for optimization of coextrusion systems. Many different types of companies, including plastic material suppliers, plastic part manufacturers and extrusion equipment manufacturers, will be able to cut cost and increase revenues using this software. Planned experimental verification of coextrusion simulation at Michigan Technological University and University of Massachusetts will benefit engineering education. The scientific knowledge developed in this project will be included in a senior-level course at Michigan Tech.