Analysing and modelling the melting behavior of planetary roller extruders

行星辊挤出机熔化行为的分析和建模

• 批准号: 192909158
• 负责人: Professor Dr.-Ing. Martin Bastian
• 金额: --
• 依托单位: Süddeutsches Kunststoff-Zentrum
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/192909158?language=en
• 关键词: Analysing; modelling; melting; behavior; planetary

Extrusion and compounding are fundamental steps in the production process of plastic products. Due to increased quality requirements and the trend to cost reduction by process optimization, the compounding process is outstandingly important. The major aim of this process step is the optimal mixing of additives with the polymer matrix. In this context, the planetary roller extruder is a machine concept that is well suited for these tasks. Reasons for this are the excellent homogenization and dispersion abilities t with a low shearing of the material as well as a narrow residence time distribution.Models that describe the process behavior of single and twin screw extruders have been discussed in the scientific and engineering literature for several years. For planetary roller extruders, first process models were published. However, these models neglect the melting process and thus they are only applicable for melt transportation.The aim of this research project is the analysis of the melting behavior of planetary roller extruders and the first time development of physical mathematical models, which describe the melting processes. Based on the successes in modeling the transport mechanism of melt fed planetary roller extruders, the approaches that are used to describe the melting process of single and twin screw extruder are adjusted to the conditions in the planetary roller extruder. The adjusted models shall make it possible to calculate the pressure, filling degree, melting degree, temperature and power consumption along the extruder length for planetary roller extruders that run as melting extruders.Because of the complexity of the topic, in the first two years only the melting behavior of unfilled polymer pellets was observed. With this simplified system the fundamentals of the modeling were created. At first an experimental setup, which enabled the analyses of melting behavior with dead stop experiments, was build. The following experiments showed, that a disperse melting model is suitable for describing the melting. This model was adapted for the planetary roller extruder and integrated in the simulation tool SimPla. First comparisons between simulations done with SimPla and experiments showed a good agreement. In the requested research project, the melting model shall be extended for powder shaped and filled materials, so that at the end of the project, a comprehensive process model for planetary roller extruders will be available.

挤出和复合是塑料制品生产过程中的基本步骤。由于质量要求的提高和通过工艺优化降低成本的趋势，配混工艺显得尤为重要。该工艺步骤的主要目的是使添加剂与聚合物基质最佳混合。在这种情况下，行星辊挤出机是一种非常适合这些任务的机器概念。其原因是优异的均化和分散能力，低剪切的物料以及窄的停留时间分布。描述单螺杆和双螺杆挤出机过程行为的模型已经在科学和工程文献中讨论了几年。对于行星式辊式挤出机，第一个工艺模型被公布。本研究的目的是分析行星式辊式挤出机的熔融行为，并首次建立描述熔融过程的物理数学模型。 在成功地建立了熔体喂料行星辊式挤出机输送机理模型的基础上，对单、双螺杆挤出机熔融过程的描述方法进行了调整，使之适用于行星辊式挤出机的情况。调整后的模型应能够计算作为熔融挤出机运行的行星辊式挤出机沿着挤出机长度的压力、填充度、熔融度、温度和功耗。由于该主题的复杂性，在前两年中仅观察了未填充聚合物颗粒的熔融行为。有了这个简化的系统，建立了建模的基础。首先，建立了一个实验装置，使熔化行为的分析与死停实验，。以下实验表明，分散熔融模型适合于描述熔融。该模型适用于行星辊挤出机，并集成在模拟工具SimPla中。第一次比较模拟与SimPla和实验显示出良好的一致性。在所要求的研究项目中，熔化模型应扩展到粉末成型和填充材料，以便在项目结束时，行星辊挤出机的综合工艺模型将可用。

项目成果

A mathematical model describing the solid conveying and melting behavior of planetary roller extruders

描述行星辊挤出机固体输送和熔化行为的数学模型

• DOI: 10.1063/1.4873850
• 发表时间: 2013
• 作者: Rudloff;Kretschmer K;Heidemeyer P;Bastian M;Koch M.
• 通讯作者: Koch M.