Thin Au/Ag/Cu-Water Nanoliquid Film Flow Over a Porous Unsteady Stretchable Cylinder

Abstract

Most of the previous works on the thin nanoliquid-film (NLF) flow on a stretchable horizontal cylinder are limited to the boundary-layer flow (BLF) of infinite depth liquid. In this article, we have removed the above restrictions to examine the unsteady thin NLF flow on a porous stretchable cylinder by considering full momentum equations under the influence of thermal radiation and suction/injection. The implicit finite difference technique is utilized to obtain the numerical solutions to the problem. The present numerical solution is validated with the analytical solution obtained by Maity et al.41 for the isothermal case. It is found that the film thickness for Au/water nanoliquid is higher in comparison with Ag/water and Cu/water nanoliquids, respectively. The film thickness of nanoliquid enhances for rising magnitude of nanoparticle volume fraction (φ), porosity parameter (β), and Hartmann number (Mn). The film thickness of the nanoliquid increases or decreases as injection or suction (V) takes place through the surface of the cylinder. Furthermore, the sign of temperature gradient θR changes inside the nanoliquid depending on the values of other parameters. The percentage of changes in the film height is presented with the different parameters of the flow problem.