Three-dimensional simulation of vortex growth within entry flow of a polymer melt
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Huan-Chang Tseng
Abstract
The corner vortex phenomenon occurring in entry flow is relevant to both polymer rheology and polymer processing. The famous viscoelastic constitutive equations in numerical computations of fluid mechanics have always had limited relevance at low apparent shear rates. However, three-dimensional (3D) simulations of viscoelastic fluids have been rarely found in advanced rheology. Recently, the GNF-X (eXtended Generalized Newtonian Fluid) constitutive equation of the weighted shear/extensional viscosity developed in advanced rheology of complex fluids has been incorporated into state-of-the-art predictive engineering tools. Thereby, 3D numerical simulations of entry flow were performed for a LDPE (low-density polyethylene) melt. As a validation, the predicted vortex streamlines are in good agreement with related experimental observations. More importantly, the simulation results show the vortex growth with respect to apparent shear rates, contraction ratios, and inlet angles. In particular for extensional viscosity, the stronger extension hardening characteristic yields a large vortex size.
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Author contributions: The author has accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: None declared.
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Conflict of interest statement: The author declares no conflicts of interest regarding this article.
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© 2022 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- Research Articles
- In-situ leakage behavior of polymer-metal hybrids under mechanical load
- Multi-objective optimization of injection molding process parameters based on BO-RFR and NSGAⅡ methods
- Effect of processing conditions on the rheological and mechanical properties of composites based on a PBS matrix and enzymatically treated date palm fibers
- Effect of additives on degradation of poly vinyl alcohol (PVA) using ultrasound and microwave irradiation
- Visualization analysis of temperature distribution in the cavity of conventional PPS and high-thermal-conductivity PPS during the filling stage of injection molding
- Conveyor belt modelling in extrusion flow simulation
- Analysis and optimization of FFF process parameters to enhance the mechanical properties of 3D printed PLA products
- Investigation of the interface behavior of a viscous fluid under free surface shear flow using an eccentric transparent Couette cell
- Effect of stacking sequence on mechanical, water absorption, and biodegradable properties of novel hybrid composites for structural applications
- Comparison of fibre reorientation of short-and long-fibre reinforced polypropylene by injection molding with a rotating mold core
- The impact of accelerated aging on the mechanical and thermal properties and VOC emission of polypropylene composites reinforced with glass fibers
- Three-dimensional simulation of vortex growth within entry flow of a polymer melt
Artikel in diesem Heft
- Frontmatter
- Research Articles
- In-situ leakage behavior of polymer-metal hybrids under mechanical load
- Multi-objective optimization of injection molding process parameters based on BO-RFR and NSGAⅡ methods
- Effect of processing conditions on the rheological and mechanical properties of composites based on a PBS matrix and enzymatically treated date palm fibers
- Effect of additives on degradation of poly vinyl alcohol (PVA) using ultrasound and microwave irradiation
- Visualization analysis of temperature distribution in the cavity of conventional PPS and high-thermal-conductivity PPS during the filling stage of injection molding
- Conveyor belt modelling in extrusion flow simulation
- Analysis and optimization of FFF process parameters to enhance the mechanical properties of 3D printed PLA products
- Investigation of the interface behavior of a viscous fluid under free surface shear flow using an eccentric transparent Couette cell
- Effect of stacking sequence on mechanical, water absorption, and biodegradable properties of novel hybrid composites for structural applications
- Comparison of fibre reorientation of short-and long-fibre reinforced polypropylene by injection molding with a rotating mold core
- The impact of accelerated aging on the mechanical and thermal properties and VOC emission of polypropylene composites reinforced with glass fibers
- Three-dimensional simulation of vortex growth within entry flow of a polymer melt
