Finite Element Modeling of a Viscous Fluid Flowing through an External Gear Pump. Issue 1 (19th October 2020)

• Record Type: Journal Article
• Authors: de Bie, Vincent G.; Hulsen, Martien A.; Anderson, Patrick D.
• Is Part Of: Macromolecular theory and simulations. Volume 30:Issue 1(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-10-19
• Subjects: external gear pumps -- finite element modeling -- residence time -- viscous fluids -- volumetric efficiency; Macromolecules -- Periodicals; Polymers -- Periodicals; Polymerization -- Periodicals; Macromolécules -- Périodiques; 547.705
• DOI: 10.1002/mats.202000060
• Languages: English
• ISSNs: 1022-1344

Abstract

Abstract: 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. Abstract : External gear pumps are used in various production systems to transport fluids. A numerical study using the finite element method shows that the efficiency of these pumps depends on material and processing parameters. The pump curve displays at which conditions the efficiency of the pump drops as a result of backflow of the fluid through the pump clearances.