Numerical visualization of extensional flows in injection molding of polymer melts
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Huan-Chang Tseng
Abstract
Extensional flows generally take place in a channel with varied cross-sectional areas. During polymer processing with a variety of complex geometric features, it is difficult to separate extensional rates from shear rates in state-of-the-art predictive engineering tools of computational fluid dynamics. The recently proposed method of Tseng [Tseng, H.-C., “A Revisitation of Generalized Newtonian Fluids,” J Rheol 64 493–504 (2020)] decomposed the generalized strain rate as the characteristic shear and extensional rates via the rate-of-deformation tensor rotated along streamline coordinates. As validation for an isothermal center-gated disk flow, the predicted flow field profiles fairly matched the analytical solution for Newtonian fluid. Under injection molding simulations, an objective indicator is defined to visualize the colorful contours of extensional flows encountered in the gate-vicinity and the mid-plane of the cavity’s thickness direction, as well as contraction-expansion channels.
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Author contributions: All the authors have 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 authors declare no conflicts of interest regarding this article.
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Articles in the same Issue
- Frontmatter
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- Time series data for process monitoring in injection molding: a quantitative study of the benefits of a high sampling rate
- Vibration damping properties of graphene nanoplatelets filled glass/carbon fiber hybrid composites
- Optical and temperature dependent electrical properties of poly (vinyl chloride)/copper alumina nanocomposites for optoelectronic devices
- Numerical visualization of extensional flows in injection molding of polymer melts
- Thermal, mechanical and dielectric properties of glass fiber reinforced epoxy-lanthanum manganite nanocomposites
- Statistical research on the mixing properties of wave based screws by numerical simulations
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- Development of a prototype for the rubber latex industry to detect dry rubber content of fresh natural rubber latex using a novel measurement system with proton-electron transfer
- Effect of molding history on molecular orientation relaxation during physical aging of polystyrene injection moldings
- A comparative analysis of the effect of post production treatments and layer thickness on tensile and impact properties of additively manufactured polymers
- Fabrication of flame-retardant and smoke-suppressant rigid polyurethane foam modified by hydrolyzed keratin
- Study on flame retardancy and thermal stability of rigid polyurethane foams modified by amino trimethylphosphonate cobalt and expandable graphite
- Three-dimensional simulation of capillary rheometry for an estimation of extensional viscosity
Articles in the same Issue
- Frontmatter
- Research Articles
- Influence of process parameters of a continuous final mixer on the properties of carbon black/rubber composites
- Time series data for process monitoring in injection molding: a quantitative study of the benefits of a high sampling rate
- Vibration damping properties of graphene nanoplatelets filled glass/carbon fiber hybrid composites
- Optical and temperature dependent electrical properties of poly (vinyl chloride)/copper alumina nanocomposites for optoelectronic devices
- Numerical visualization of extensional flows in injection molding of polymer melts
- Thermal, mechanical and dielectric properties of glass fiber reinforced epoxy-lanthanum manganite nanocomposites
- Statistical research on the mixing properties of wave based screws by numerical simulations
- Influence of mold cavity thickness on electrical, morphological and thermal properties of polypropylene/carbon micromoldings
- Development of a prototype for the rubber latex industry to detect dry rubber content of fresh natural rubber latex using a novel measurement system with proton-electron transfer
- Effect of molding history on molecular orientation relaxation during physical aging of polystyrene injection moldings
- A comparative analysis of the effect of post production treatments and layer thickness on tensile and impact properties of additively manufactured polymers
- Fabrication of flame-retardant and smoke-suppressant rigid polyurethane foam modified by hydrolyzed keratin
- Study on flame retardancy and thermal stability of rigid polyurethane foams modified by amino trimethylphosphonate cobalt and expandable graphite
- Three-dimensional simulation of capillary rheometry for an estimation of extensional viscosity
