Mon, December 16, 2019   Advanced Search

A Numerical Study on Unsteady Natural Convection Flow with Temperature Dependent Viscosity past an Isothermal Vertical Cylinder

Md. A Hossain1, R. K. Mondal2, R. Ahmed3 and S. F. Ahmmed4

1-4Mathematics Discipline, Khulna University, BANGLADESH. e-mail:,,,


Aim of this paper is to investigate the boundary layer flow and heat transfer of unsteady laminar free convection flow past a semi-infinite isothermal vertical cylinder immersed in air. The fluid viscosity is adopted to vary the temperature. An explicit finite difference method has been devoted to solve the governing nondimensional boundary layer equations. A parametric study is accomplished to interpret the influence of variable viscosity on the velocity and temperature profiles. The numerical consequences disclose that the viscosity has significant influence on transient velocity and temperature profiles, average skin friction coefficient and average heat transfer rate. The conclusion indicates that when the viscosity parameter increases the temperature and skin friction coefficient increases but the velocity near the wall and Nusselt number decreases. We have also shown the effect of viscosity variation parameter on isotherms and streamlines

Keywords : Heat transfer, Natural convection, Variable viscosity, Vertical cylinder, Explicit finite difference method