| Summary: | In the present study, thermofluidic characteristics of a combined pressure-driven and electrical field mediated thermally fully developed flow of an immiscible Newtonian and a viscoelastic fluid bi-layer in a microchannel have been analyzed. The simplified Phan-Thien-Tanner model with a linear kernel for the stress coefficient function has been utilized to describe the complex fluid rheology for the non-Newtonian fluid. Disparate zeta potentials have been assumed at the interfaces. Accordingly, distinct zeta potential values have been used at the channel walls and interfaces between the fluids to derive the closed-form analytical expressions for the pertinent velocity, stress, and shear viscosity distributions in the fluid layers. For thermally developed flows, the temperature and entropy distributions are obtained along the microchannel for constant wall heat flux boundary conditions. Major findings from our research show that amplification of the viscoelastic parameter designated by the Weissenberg number exhibits an enhancement in the non-dimensional axial velocity, flow rate, and stress magnitudes. Furthermore, the present study indicates that Joule heating and viscous dissipation significantly vary the dimensionless temperature profiles along the fluid bi-layer. The Nusselt number values are found to decrease with the augmentation of the viscoelasticity, Joule heating, and viscous dissipation parameters. The total entropy generation for the fluid layer systems increases with the increasing Joule heating parameter. © 2022 Author(s).
|
|---|
