Gear pumps are frequently used for the transport of high‐viscosity fluids, for instance, for the extrusion of polymers. The flow rate of this extrusion process is regularly controlled by an external gear pump. In this work, the 2D flow of a viscous fluid through such an external gear pump is studied using the finite element method. Local mesh refinement based on the respective distance between moving boundaries is essential to capture the relatively narrow clearances in the pump. The gear pump works against the pressure driven flow, therefore its performance is strongly dependent on material and processing parameters. The flow of Newtonian and shear‐thinning fluids through the external gear pump is studied for a range of processing conditions. Pump curves are obtained that display the volumetric efficiency against the Hersey number, which is defined as viscosity times rotation speed divided by pressure difference over the pump. Analysis of the residence time of the fluid in the pump, shows that vortices are present in the inflow channel causing material to remain in the pump for longer times.

中文翻译：

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流经外齿轮泵的粘性流体的有限元建模

齿轮泵通常用于输送高粘度流体，例如用于挤出聚合物。挤出过程的流量由外齿轮泵定期控制。在这项工作中，使用有限元方法研究了粘性流体通过此类外齿轮泵的二维流动。基于运动边界之间的各自距离的局部网格细化对于捕获泵中相对较窄的间隙至关重要。齿轮泵与压力驱动的流量相反，因此其性能在很大程度上取决于材料和加工参数。在一系列加工条件下，研究了牛顿流体和剪切稀化流体通过外齿轮泵的流动。获得的泵曲线显示了相对于赫尔西数的容积效率，定义为粘度乘以转速除以泵上的压差。对泵中流体停留时间的分析表明，流入通道中存在涡流，导致物料在泵中停留的时间更长。