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

固体输送是塑料挤出成型的重要工艺环节。在本提案中，将研究并模拟高螺杆速度（考虑压力累积）。描述单螺杆挤出机中的固体输送的公知模型假定完全填充的螺杆通道和活塞流。然而，在高螺杆速度下，这些假设不再有效。因此，通道填充和固体输送吞吐量的研究在这个建议中使用离散元模拟，它允许考虑单个颗粒的运动。固体输送模型，基于这样的DEM模拟和发现在以前的建议是扩展到也考虑压力的建立。为了能够准确地模拟压力积聚，必须确定适当的材料模型和合适的模拟参数。之后进行的模拟验证实验固体输送调查。因此，必须建立一个立场。最后，计划进一步优化料斗开口几何形状，以减少众所周知的再循环现象，该现象发生在料斗开口中，并在高螺杆速度下变得重要。这一优化也将基于以前的研究成果的建议。

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 At high screw speeds however, these assumptions are no longer valid.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.