Computational fluid dynamics study of polyethylene/ ethylene vinyl acetate blend morphology development in a spinneret by volume of fluid method

Mohammadzadeh Pakdel, Parisa; Yegani, Reza; Salami Hosseini, Mahdi; Shokri, Elham

doi:10.22063/poj.2025.35626.1344

Computational fluid dynamics study of polyethylene/ ethylene vinyl acetate blend morphology development in a spinneret by volume of fluid method

Document Type : Original research

Authors

Parisa Mohammadzadeh Pakdel ¹^{, 2}

Reza Yegani ¹^{, 2}

Mahdi Salami Hosseini ³^{, 2}

Elham Shokri ⁴

¹ Faculty of Chemical Engineering, Sahand University of Technology, Sahand New Town, Tabriz, Post box: 51335/1996, Iran

² Membrane Technology Research Center, Sahand University of Technology, Sahand New Town, Tabriz, Post box: 51335/1996, Iran

³ Faculty of Polymer Engineering, Sahand University of Technology, Sahand New Town, Tabriz, Post box: 51335/1996, Iran

⁴ Department of Chemical Engineering, University of Bonab, Bonab, Iran

https://doi.org/10.22063/poj.2025.35626.1344

Abstract

In the current study, the flow field and morphology development of a polyethylene (PE) and ethylene vinyl acetate (EVA) blend were investigated numerically during extrusion through a spinneret using Fluent 6.3.26 software. The interface of the two phases was tracked using the volume of fluid (VOF) method. In a conventional spinneret, EVA droplets near the walls break up due to the high shear rate, while the central droplet deforms without breaking up. To enhance the breakup of EVA droplets, the effects of device geometry, including the spinneret angle and the presence of one or two lamps, were investigated in detail. The numerical results indicated that a decrease in the spinneret angle from 60° to 45° causes the central droplet to become more elongated in the flow direction. Additionally, the results showed that the presence of one or two lamps in the conical zone of the spinneret causes a portion of the central droplet to break up.

Graphical Abstract

Keywords

Spinneret

morphology

computational fluid dynamics

Flow field

VOF method

Subjects

Utracki LA, Shi ZH (2004) Development of polymer blend morphology during compounding in a twin‐screw extruder. Part I: Droplet dispersion and coalescence: A review. Polym Eng Sci 32: 1824-1833 [CrossRef]
Yong WF, Zhang H (2020) Recent advances in polymer blend membranes for gas separation and pervaporation. Prog Mater Sc 116: 100713 [CrossRef]
Kadanyo S, Gumbi NN, Matindi CN, Dlamini DS, Hu Y, Cui Z, Wang H, Hu M, Li J (2022) Enhancing compatibility and hydrophilicity of polysulfone/poly (ethylene-co-vinyl alcohol) copolymer blend ultrafiltration membranes using polyethylene glycol as hydrophilic additive and compatibilizer. Separ Purif Technol 287: 120523 [CrossRef]
Fortelný I, Živný A (2003) Extensional flow induced coalescence in polymer blends. Rheol Acta 42: 454-461 [CrossRef]
Velayutham TS (2024) Miscibility and immiscibility in PVC-based blends, IPNs, and gels. In: Poly(vinyl chloride)-based blends, IPNs, and gels, Elsevier, pp: 377-400 [CrossRef]
Xiang S, Tang X, Rajabzadeh S, Zhang P, Cui Z, Matsuyama H (2022) Fabrication of PVDF/EVOH blend hollow fiber membranes with hydrophilic property via thermally induced phase process. Separ Purif Techno 301: 122031 [CrossRef]
Perera HS, Ernst KJ, Tafreshi HV, Khan SA (2024) Viscoelastic fluid stresses in the formation and shaping of melt-spun hollow fibers. ACS Appl Eng Mater 3: 75-84 [CrossRef]
Wilczyński K, Tyszkiewicz A, Szymaniak Z (2002) Modeling for morphology development during single-screw extrusion of LDPE/PS blend. J Mater Process Technol 109: 320-323 [CrossRef]
Tanpaiboonkul P, Lerdwijitjarud W, Sirivat A, Larson RG (2007) Transient and steady-state deformations and breakup of dispersed-phase droplets of immiscible polymer blends in steady shear flow. Polymer 48: 3822-3835 [CrossRef]
Janssen J, Meijer H (2002) Droplet breakup mechanisms: Stepwise equilibrium versus transient dispersion. J Rheol 37: 597-608 [CrossRef]
Shilton SJ (2002) Flow profile induced in spinneret during hollow fiber membrane spinning. J Appl Polym Sci 65: 1359-1362 [CrossRef]
Chung TS, Qin JJ, Gu J (2002) Effect of shear rate within the spinneret on morphology, separation performance and mechanical properties of ultrafiltration polyethersulfone hollow fiber membranes. Chem Eng Sci 55: 1077-1091 [CrossRef]
Qin JJ, Wang R, Chung TS (2002) Investigation of shear stress effect within a spinneret on flux, separation and thermomechanical properties of hollow fiber ultrafiltration membranes. J Membrane Sci 175: 197-213 [CrossRef]
Cao C, Chung TS, Chen SB, Dong ZJ (2004) The study of elongation and shear rates in spinning process and its effect on gas separation performance of Poly(ether sulfone) (PES) hollow fiber membranes. Chem Eng Sci 59: 1053-1062 [CrossRef]
Selvam K, Suresh K, Karunanithi B (2021) Assessment of the flow behavior of power-law fluids in spinnerets. Chem Eng Res Des 176: 134-145. [CrossRef]
Ning H, Qian S, Zhou T (2023) Applications of level set method in computational fluid dynamics: A review. Intl J Hydromechatronics 6: 1 [CrossRef]
Fakhreddine A (2024) Numerical simulation and modeling of two-phase flows using the volume-of- fluid method, University of Minnesota, Ph.D. dissertation
Li B, Zhang H, Fu S, Su W, Wang Y, Wang L (2024) Simulation of single droplet deformation and breakup in shear flow by the phase-field lattice Boltzmann method. Ind Eng Chem Res 63: 22104-22117 [CrossRef]
Deng C, Wang H, Huang W, Cheng S (2017) Numerical and experimental study of oil-in-water (O/W) droplet formation in a co-flowing capillary device. Colloids Surf A: Physicochem Eng Asp 533: 1-8 [CrossRef]
Aloku GO, Yuan XF (2010) Numerical simulation of polymer foaming process in extrusion flow. Cheml Eng Sci 65: 3749-3761[CrossRef]
Pan D, Zhang Y, Zhang T, Li B (2021) Flow regimes of polymeric fluid droplet formation in a co-flowing microfluidic device. Colloid Interface Sci Commun 42: 100392 [CrossRef]
Zhang T, Shao T, Zhang Y, Pan D, Huang W, Li B (2021) Effect of interface deformation on hydrodynamics of liquid–liquid two-phase flow in a confined microchannel. Chem Eng J 427: 131956 [CrossRef]