Computation of Eyring-Powell micropolar convective boundary layer flow from an inverted non-isothermal cone : thermal polymer coating simulation

Gaffar, SA; Khan, BMH; Beg, OA; Kadir, A; Prasad, VR

Abstract

Thermal coating of components with non-Newtonian materials is a rich area of chemical and process
mechanical engineering. Many different rheological characteristics can be simulated for such coatings with a
variety of different mathematical models. In this work we study the steady-state coating flow and heat transfer
of a non-Newtonian liquid (polymer) on an inverted isothermal cone with variable wall temperature. The
Eringen micropolar and three-parameter Eyring-Powell models are combined to simulate microstructural and
shear characteristics of the polymer. The governing partial differential conservation equations and wall and free
stream boundary conditions are rendered into dimensionless form and solved computationally with the KellerBox finite difference method (FDM). Validation with earlier Newtonian solutions from the literature is also
included. Graphical and tabulated results are presented to study the variations of fluid velocity, micro-rotation
(angular velocity), temperature, skin friction, wall couple stress (micro-rotation gradient) and wall heat transfer
rate. With increasing values of the first Eyring-Powell parameter temperatures are elevated, micro-rotation is
suppressed and velocities are enhanced near the cone surface but reduced further into the boundary layer.
Increasing values of the second Eyring-Powell parameter induce strong flow deceleration, decrease temperatures
but enhance micro-rotation values. An increase in non-isothermal power law index suppresses velocities,
temperatures and micro-rotations i.e. all transport characteristics are maximum for the isothermal case (n =0).
Increasing Eringen vortex viscosity parameter significantly enhances temperatures and also micro-rotations. The
present numerical simulations find applications in thermal polymer coating operations and industrial deposition
techniques and provide a useful benchmark for more general computational fluid dynamics (CFD) simulations.

Citation

Gaffar, S., Khan, B., Beg, O., Kadir, A., & Prasad, V. (2020). Computation of Eyring-Powell micropolar convective boundary layer flow from an inverted non-isothermal cone : thermal polymer coating simulation. Computational Thermal Sciences, 12(4), 329-344. https://doi.org/10.1615/ComputThermalScien.2020033860

• Journal Article Type: Article
• Acceptance Date: May 26, 2020
• Online Publication Date: Jul 30, 2020
• Publication Date: Jul 30, 2020
• Deposit Date: May 27, 2020
• Publicly Available Date: Jul 30, 2021
• Journal: Computational Thermal Sciences: An International Journal
• Print ISSN: 1940-2503
• Electronic ISSN: 1940-2554
• Publisher: Begell House
• Volume: 12
• Issue: 4
• Pages: 329-344
• DOI: https://doi.org/10.1615/ComputThermalScien.2020033860
• Publisher URL: https://doi.org/10.1615/ComputThermalScien.2020033860
• Related Public URLs: http://www.begellhouse.com/journals/648192910890cd0e