Modeling the solid conveying section of single-screw extruders at high screw speeds considering the pressure build-up

考虑压力积聚，对单螺杆挤出机在高螺杆速度下的固体输送部分进行建模

• 批准号: 242845944
• 负责人: Professor Dr.-Ing. Volker Schöppner
• 金额: --
• 依托单位: Fachgebiet Kunststoffverarbeitung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/242845944?language=en
• 关键词: Modeling; solid; conveying; section; single

Solid conveying is an important process part of plastic extrusion. In this proposal it is to be investigated and modelled up to high screw speeds considering the pressure build-up. Commonly known models describing the solid conveying in single screw extruders assume a fully filled screw channel and a plug flow. At high screw speeds however, these assumptions are no longer valid. Therefore, the channel filling and the solid conveying throughput are investigated in this proposal using Discrete-Element-Simulations, which allow the consideration of single particles motions. The solid conveying model, based on such DEM simulations and found in the previous proposal is to be extended to also considering the pressure build-up. To be able to simulate the pressure build-up accurately, an appropriate material model and suitable simulation parameters have to be determined. Afterwards the conducted simulations are validated by experimental solid conveying investigations. Therefore, a stand has to be constructed. Finally, a further optimization of the hopper opening geometry is scheduled in order to reduce the well-known recirculation phenomenon which takes place in the hopper opening and becomes important at high screw speeds. This optimization will also be based on the previous proposals research results.

固体输送是塑料挤出的重要工艺环节。在这项建议中，考虑到压力的积累，将对其进行研究并模拟为高螺杆速度。通常，描述单螺杆挤出机中固体输送的模型假定螺杆通道和塞流是完全充满的。然而，在高螺杆速度下，这些假设不再有效。因此，在该方案中，使用离散元模拟来研究通道填充和固体输送吞吐量，该离散元模拟允许考虑单粒子运动。基于这种DEM模拟的固体输送模型将被扩展到也考虑压力积累的情况。为了能够准确地模拟压力积累，必须确定合适的材料模型和合适的模拟参数。之后，通过固体输送实验研究对所进行的模拟进行了验证。因此，必须建立一个摊位。最后，对料斗开口的几何形状进行了进一步的优化，以减少众所周知的再循环现象，这种现象发生在料斗开口中，在高螺杆转速下变得重要。本次优化也将基于前人的建议研究成果。