Heat transfer is quietly related to the thermophysical properties of fluid and similarly the potentials to increase the thermal conductivity of conventional working fluid is quite interesting. Indeed, the increasingly demands to enhance heat dissipation, cooling/heating processes as well as saving energy, time and cost of production in the industrial system has been a challenge to many engineers and scientists. In view of this, mathematical modelling for free convective flow in a viscoelastic fluid past a nonlinear vertical stretching sheet with thermal radiation effect is considered and analysed in this paper. Using a proper similarity transformation that differs from that of linear stretching sheet problem, the conservation, momentum and heat transfer equations are reduced into coupled ordinary differential equations. The reduced equations are solved numerically via Keller box method. A detailed evaluation of the effects of the governing physical parameters on the velocity field and temperature distributions through graphical plots and tabular form are presented for power law heat flux condition. It is observed that heat transfer is enhanced with the increase in the value of viscoelastic parameter and reduces with the increase in the Grashof and Prandtl numbers.
Key words: Boundary layer flow, Viscoelasticity, Nonlinear stretching sheet, Free convection and Thermal radiation
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