Abstract:
The thermal-dIffusion and diffusion-thermo effects on Magnetohydrodynamics (MAD)
heat and mass transfer boundary layer flow have been studied numerically. The
governing equations are then made dImensionless by I.lsing I.lsual similarity
transformations. The dimensionless equations are solved numcneally by applying
Nachtsheim-Swlgert shooting iteration techmque along with Rungc-Kmta sixth order
integration method.
A two-dimensional steady MHD combined free-forced convedion and mass transfer flow
past a semi-infmlte vertical plate is investigated. The effects of magnelle parameter M,
thermal-diffusion parameter Sr (Soret numher) and diffusion-thermo parameter Df
(Dufol.lr numher) have been examined on the 110wfield of a hydrogen-air mixture as. a
non-chemical reactmg fluid pair. The analysis has shown that the 110w field is
appreciably influenced by the thermal-dIffusion and diffusion-thermo effects. In our
study we have also found that the present results are in excellent agreement with
Kafoussia~ (1990), when M == Df == Sr = O.
Next, the above effects have been analyzed on unsteady MHD free convection and mass
flow pa~t an mfinite vertical porous plate. Two eases are considered (I) Impulsively
started plate (ISP) and (ii) Uniformly accelerated plate (UAP). Similarity equal10ns of the
momentum, energy and concentration equations are derived by mtroducing a time
dependent length scale. The dimensionless velocity, temperature and concentration
profiles are shown graphically for different values of the parameters entenng into the
problem. The numerical valLlCsof the local skm-friction, local Kusselt number and local
Shelwood number are aho presented in tabular form.
