Design and Optimization of Wave-Dispersion Screws

内容：单螺杆挤出机无疑是聚合物加工工业中最重要的机器。在塑化挤出过程中，聚合物以固态的形式被送入挤出机，物料在旋转的挤出机螺杆从进料口输送到模具的过程中被熔化。基于经济框架，机器制造商的首要目标是在保证高熔体质量的同时增加产量。满足这些要求需要适当的螺杆设计，从而对控制挤出过程的输送现象有透彻的了解。这个牵头机构的研究项目将重点研究固体床破碎螺钉的概念，详细研究波色散螺钉。为了增加对波弥散螺杆复杂过程的理解，将借助3d - cfd - simulation开发新的过程模型，并通过在光滑筒体（KTP）和槽筒体（IPEC）单螺杆挤出机上进行的实验研究进行验证，涵盖广泛的可能的挤出过程。与现有的过程行为简化模型相比，这将提高波色散螺钉的建模精度，从而为波色散螺钉的螺旋优化提供了潜力，使它们能够充分发挥其潜力。假设和方法：3d - cfd -模拟将以两种不同的方式进行。一方面，通过许多以熔体为主导的弯曲螺旋通道模拟，生成了数据驱动的压力/吞吐量模型。另一方面，引入了考虑固体材料熔化的非等温3D-CFD模拟模型，并将其用于分析不同的波频散螺杆。此外，还对常用材料类型的波色散螺杆加工提出了设计准则。这将有助于满足单螺杆挤出领域对产量和熔体质量的高要求。此外，还将对各种45mm单螺杆挤出机进行实验研究，以验证这些模型。创新和新颖性：少数涉及上述主题的科学论文仍然留下了许多未解之谜，并表明本建议的内容是高度相关的。研究表明，波色散螺杆可以提高熔体的吞吐量和均匀性，但目前设计螺杆的解析计算模型精度较低。由于所研究的螺杆概念必须精心设计，以展现其全部优势，其目的是合并KTP， Paderborn和IPEC， Linz的建模和仿真领域的专业知识，以产生新的建模方法，大大提高预测的准确性。因此，成功和可靠地设计和使用波色散螺钉将是可能的。

Content:Single-screw extruders are indisputably the most important machines in the polymer processing industry. During plasticating extrusion, polymer is fed to the extruder in the solid-state and the material is melted as it is conveyed by the rotating extruder screw from the feed port to the die. Based on the economic framework, the primary objective of machine manufacturers is to increase the output capacity while guaranteeing high melt quality. Meeting these demands requires proper screw design and thus a thorough understanding of the transport phenomena governing the extrusion process. Focusing on solid bed breaking screw concepts, this lead-agency research project will investigate wave-dispersion screws in detail. To increase the understanding for the complex processes in wave-dispersion screws, new process models will be developed with the help of 3D-CFD-Simulations and validated by experimental studies carried out on smooth-barrel (KTP) as well as grooved-barrel (IPEC) single screw extruders, covering a wide range on possible extrusion processes. This will increase the modeling accuracy of wave-dispersion screws in comparison to existing simplified models of the process behavior and thus give potential for screw optimization of wave-dispersion screws so that they can exploit their full potential.Hypothesis and methods:3D-CFD-Simulations will be carried out in two different ways. On the one hand, a data driven pressure/throughput model is generated by means of many melt-dominated curved screw channel simulations. On the other hand, a non-isothermal 3D-CFD simulation model, which also considers the melting of the solid material, is introduced and used for the analysis of the different wave-dispersion screws. Furthermore, design guidelines for common material types processed on wave-dispersion screws are developed. This will help to meet the high demands in terms of output capacity and melt quality in the field of single-screw extrusion. Additionally, experimental studies will be carried out on various 45mm single-screw extruders to validate these models.Innovation and novelty:The few scientific papers dealing with the above-mentioned topic still leave many questions unanswered and show that the contents of this proposal are highly relevant. It has been shown, that wave-dispersion screws can lead to higher throughput and better melt homogeneity, but the analytical calculation models for designing a screw have a lack of precision. Since the investigated screw concept must be meticulously designed in order to unfold its full advantages, the aim is to merge the expertise in the field of modeling and simulation of the KTP, Paderborn and the IPEC, Linz to produce new modeling approaches that considerably increase the accuracy of the predictions. As a result, a successful and trustful design and use of the wave-dispersion screws will be possible.