Abstract
It is difficult to directly measure the steady extensional viscosity of thermoplastic composite materials, especially at high extension rates. The famous Cogswell method was derived analytically from the pressure drop of entrance flow in commercial capillary rheometers for estimating the extensional viscosity. However, using Cogswell´s extensional viscosity has always resulted in over-predictions of pressure drop. Recently, the GNF-X (eXtended Generalized Newtonian Fluid) model with a weighted shear/extensional viscosity was proposed to show the typical extension-induced vortex growth in entrance flow simulations. Under given various values of Trouton’s ratio for extensional viscosity, the GNF-X model is introduced to perform three-dimensional flow simulations of capillary rheometry over a range of apparent shear rates. The difference between the predicted pressure drops and the relevant experimental data is minimized such that the estimation of extensional viscosity is optimized herein.
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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
- 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
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