The Boundary Layers of an Unsteady Stagnation Points Flow  in Carbon Nanotubes

Dhurgham Allaw; Norfifah Bachok; Norihan Md Arifin; Fadzilah Md Ali

Authors

Dhurgham Allaw Institute for Mathematical Research, Univirsiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
Norfifah Bachok Department of Mathematics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Malaysia
Norihan Md Arifin Department of Mathematics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Malaysia
Fadzilah Md Ali Institute for Mathematical Research, Univirsiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia

Keywords:

Unsteady boundary layer, Carbon Nanotubes, Stagnation point flow, Dual solutions

Abstract

The unsteady stagnation-point boundary layer flow of carbon nanotubes is studied. Single-wall and multi-wall of carbon nanotubes are considered with H20 as a carrier fluid. The compatible transformations are utilized to change the governing equations of mathematical model which is in the form of partial differential equations (PDEs) into a set of a non-linear ordinary differential equations (ODEs ). Solution of the problem obtained numerically through a powerful function (bvp4c) in MATLAB software. The impact of solid volume fraction and unsteadiness parameters on dimensionless velocity and temperature flow fields along with the magnitude of skin friction coefficient and local Nusselt number are discussed graphically and interpreted physically. The outcome indicates that the dual solutions observed when unsteadiness parameter is negative. Further, single-wall carbon nanotube has higher skin friction, as well as heat transfer rate, compare with multi-wall carbon nanotube at the surface.