Dynamics of viscoelastic fluid in a rotating soft microchannel

• Published in: Physics of fluids (1994) Vol. 32; no. 11
• Main Authors: Balasubramanian, Srikumar, Kaushik, P., Mondal, Pranab K.
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 01.11.2020
• Subjects: Centrifugal force; Coriolis force; Drag; Dynamics; Finite difference method; Fluid flow; Induced drag; Iterative methods; Linear algebra; Mathematical models; Microchannels; Microfluidic devices; Numerical models; Partial differential equations; Rheological properties; Rotating fluids; Velocity distribution; Viscoelastic fluids; Viscoelasticity
• ISSN: 1070-6631; 1089-7666
• DOI: 10.1063/5.0025157

In this study, we numerically investigate the effects of rotational forces, viz., centrifugal force and Coriolis force, on the flow dynamics of a viscoelastic fluid in a polymeric layer grafted microchannel. The viscoelastic fluid is represented by the Oldroyd-B model, and the effect of viscoelasticity on the underlying transport is studied. A numerical procedure consistent with the finite difference method is used to solve the system of partial differential equations. The numerical model takes into consideration, among many others, the drag effects of the “soft layer” and the transiences in the flow dynamics leading to the steady state. The complex interplay between the effect of rotational forcing and the presence of the soft layer is observed to lead to vital conclusions that could improve the design of many lab-on-a-compact disc based microfluidic devices. In addition, the effect of elasticity on the flow dynamics in the presence of rotational forces and soft layer induced drag force is studied. The in-house numerical code employs the finite difference numerical scheme to discretize the equations and consequently solves the obtained system of linear algebraic equations using the Gauss–Seidel iterative scheme. By demonstrating the velocity profiles, we discuss the effect of the various rheological parameters on the underlying transport feature. Finally, the effect of the rotation on the net throughput is studied extensively.