Optimierung und Modellierung der geometrischen Gestaltung der Einzugszone bei einem Einschneckenextruder im Hochgeschwindigkeitsbereich

单螺杆塑化领域的新发展的特点是不断努力提高工艺的经济效益，同时保证高熔体质量。通常，这意味着相同大小的机器的吞吐量增加。在过去的几十年中，与螺杆直径相关的吞吐量显著增长。凹槽衬套、更强大的传动装置和优化的螺杆几何结构的使用大大促进了这一发展。但是这种方法已经达到了极限，可以通过提高螺杆的转速来进一步提高机器的吞吐量(不增加螺杆直径)。通过将输入的能量从扭矩转换为转速，还可以使用直接的无齿轮传动，从而避免变速箱的损失。此外，通过减少与产量相关的热损失的表面积，降低了挤出机的功率消耗。这类机器的尺寸缩小是另一个显著的好处。更大的优势来自较小的通道体积，因为它减少了材料的停留时间。这导致材料降解更少，材料和工作点的变化更快。然而，高速机器方法受到工艺工程的限制。必须考虑的一些方面包括料斗供料不佳、输出脉冲的进料不均匀以及熔体温度过高。特别是，由于停留时间极短，熔融行为也起到了重要作用。到目前为止，大多数关于高螺杆转速的研究工作都集中在半结晶热塑性塑料(特别是聚烯烃，如PE和PP)上。因此，大多数研究结果都源于这些材料的特殊性质。到目前为止，对非晶态热塑性塑料的研究结果还很少。由于非晶态热塑性塑料的结构与半结晶热塑性塑料不同，非晶态热塑性塑料在固体输送、熔融和材料降解等方面的加工特性也有所不同。本研究项目的目的是通过分析非晶态热塑性塑料在高螺杆转速(2100rpm)下加工过程中的物理效应，了解非晶态热塑性塑料的加工过程，并制定加工设计规则。为此，将进行实验研究。将检查工艺数据以及产品(薄膜)的机械和光学性能。提取的结果将通过紧密聚焦的模拟方法进行分析，以得出针对所考虑的材料的工艺设计标准。为了验证这些结果，将根据这些标准设计和测试优化的螺杆。

New developments in the field of single screw plastification are characterised by continually endeavouring to raise the process' economic efficiency and to simultaneously guarantee a high melt quality. As a rule, this signifies an increase in the throughput for the same size of machine. The screw diameter related throughput has grown significantly in the past decades. Grooved bushes, more powerful drives and the use of optimised screw geometries have substantially contributed to this development. But this approach has come to its limits.A further increase in the throughput of a machine (without increasing the screw diameter) can be obtained by increasing the screw's rotational speed. Shifting the energy input from the torque to the rotational speed also enables direct, gearless drives to be used so that gearbox losses can be avoided. Besides this, the extruder's power consumption is lowered by means of the reduced surface area for throughput-related heat loss. The reduced size of such machines is another significant benefit. Further advantages result from the smaller channel volumes since it reduces the material's residence time. This results in less material degradation and faster changes of the material and the operating point.However, the high-speed machine approach is subject to process engineering limitations. A poor hopper feed-supply of the material, a non-uniform material feed with pulsing output and too high melt temperatures are some of the aspects which must be taken into account. In particular, the melting behaviour also plays an important role owing to the extremely short residence times. Up to now most research work with reference to high screw speeds was focused on semi-crystalline thermoplastics (especially polyolefins like PE and PP). Hence most findings result from the specific properties of these materials.So far only a few results exist for amorphous thermoplastics. Due to a different structure compared to semi-crystalline thermoplastics, the processing characteristics of amorphous thermoplastics concerning solids conveying, melting and material degradation differ.The aim of this research project is to understand the process and develop design rules for processing amorphous thermoplastics by analyzing physical effects during the processing of these materials at high screw speeds (2100rpm). To this experimental investigations will be carried out. Process data will be examined as well as the mechanical and optical properties of the product (film). The extracted results will be analyzed by tightly focused simulative Methods to educe criteria to design process for the considered materials. To verify these results an optimized screw will be designed and tested with these criteria.