scholarly journals Thermal Radiation and Buoyancy Effects on Heat and Mass Transfer over a Semi-Infinite Stretching Surface with Suction and Blowing

2008 ◽  
Vol 2008 ◽  
pp. 1-12 ◽  
Author(s):  
S. Shateyi

This study sought to investigate thermal radiation and buoyancy effects on heat and mass transfer over a semi-infinite stretching surface with suction and blowing. Appropriate transformations were employed to transform the governing differential equations to nonsimilar form. The transformed equations were solved numerically by an efficient implicit, iterative finite-difference scheme. A parametric study illustrating the influence of wall suction or injection, radiation, Schmidt number and Grashof number on the fluid velocity, temperature and concentration is conducted. We conclude from the study that the flow is appreciably influenced by thermal radiation, Schmidt number, as well as fluid injection or suction.

2016 ◽  
Vol 3 (4) ◽  
pp. 349-362 ◽  
Author(s):  
R. Srinivasa Raju ◽  
G. Jithender Reddy ◽  
J. Anand Rao ◽  
M.M. Rashidi

Abstract The numerical solutions of unsteady hydromagnetic natural convection Couette flow of a viscous, incompressible and electrically conducting fluid between the two vertical parallel plates in the presence of thermal radiation, thermal diffusion and diffusion thermo are obtained here. The fundamental dimensionless governing coupled linear partial differential equations for impulsive movement and uniformly accelerated movement of the plate were solved by an efficient Finite Element Method. Computations were performed for a wide range of the governing flow parameters, viz., Thermal diffusion (Soret) and Diffusion thermo (Dufour) parameters, Magnetic field parameter, Prandtl number, Thermal radiation and Schmidt number. The effects of these flow parameters on the velocity (u), temperature (θ) and Concentration (ϕ) are shown graphically. Also the effects of these pertinent parameters on the skin-friction, the rate of heat and mass transfer are obtained and discussed numerically through tabular forms. These are in good agreement with earlier reported studies. Analysis indicates that the fluid velocity is an increasing function of Grashof numbers for heat and mass transfer, Soret and Dufour numbers whereas the Magnetic parameter, Thermal radiation parameter, Prandtl number and Schmidt number lead to reduction of the velocity profiles. Also, it is noticed that the rate of heat transfer coefficient and temperature profiles increase with decrease in the thermal radiation parameter and Prandtl number, whereas the reverse effect is observed with increase of Dufour number. Further, the concentration profiles increase with increase in the Soret number whereas reverse effect is seen by increasing the values of the Schmidt number. Highlights Studied MHD free convection Couette flow with the effect of Soret & Dufour numbers. Finite Element Method is implemented as the numerical approach. Grid independence of FEM is studied. Enhance the fluid velocity as increasing of temperature and concentration gradient.


Author(s):  
S. M. M. EL-Kabeir ◽  
Ali Chamkha ◽  
A. M. Rashad

The thermal-diffusion and diffusion-thermo effects on heat and mass transfer by magnetohydrodynamic (MHD) mixed convection stagnation-point flow of a power-law non-Newtonian fluid towards a stretching surface in the presence of a magnetic field, thermal radiation and homogenous chemical reaction effects have been studied. A suitable set of dimensionless variables is used and similar equations governing the problem are obtained. The resulting equations have the property that they reduce to various special cases previously considered in the literature. An adequate implicit tri-diagonal finite-difference scheme is employed for the numerical solution of the obtained equations. Various comparisons with previously published work are performed and the results are found to be in excellent agreement. Representative results for the velocity, temperature, and concentration profiles as well as the local skin-friction coefficient, the local Nusselt number and the local Sherwood number illustrating the influence of the magnetic parameter, power-law fluid index, mixed convection parameter, concentration to thermal buoyancy ratio, thermal radiation, chemical reaction, and Dufour and Soret numbers are presented and discussed.


2015 ◽  
Vol 127 ◽  
pp. 1315-1322 ◽  
Author(s):  
Manjula Jonnadula ◽  
Padma Polarapu ◽  
Gnaneswara Reddy M ◽  
Venakateswarlu. M

Sign in / Sign up

Export Citation Format

Share Document