lass="cs_fig_con">Figure 2. Velocity profiles when Sc = 2.01, Pr = 0.71, M = 3, k = 5, Du = 0.03 & t = 0.4.

Figure 3. Velocity profiles when Sc = 2.01, Pr = 0.71, R = 10, k = 5, M = 3 & t = 0.4.

Figure 4. Velocity profiles when M = 3, Pr = 0.71, Sc = 2.01, R = 10, k = 5, Du = 0.03 & t = 0.4.

Figure 5. Velocity profiles when M = 4, Pr = 0.71, R = 10, k = 5, Du = 0.03 & t = 0.4.

Figure 6. Velocity profiles when Sc = 2.01, M = 3, Pr = 0.71, R = 10, k = 5, Du = 0.03.

Figure 7. Velocity profiles when Sc = 2.01, Pr = 0.71, R = 10, M = 3, Du = 0.03 & t = 0.4.

Figure 8. Temperature profiles when R = 4, Pr = 0.71 & Sc = 2.01.

Figure 9. Temperature profiles when Du = 0.03, Pr = 0.71 & Sc = 2.01.

Figure 10. Temperature profiles when R = 4, Du = 0.03 & Sc = 2.01.

Figure 11. Concentration profiles.

Figure 12. Nusselt number.

Figure 13. Sherwood number.

effects of Prandtl number Pr on the temperature field. It is observed that an increase in the Prandtl number leads to decrease in the fluid temperature. It is due to the fact that thermal conductivity of the fluid decreases with increasing Pr, resulting a decrease in thermal boundary layer thickness.

The concentration profiles for different values of Schmidt number (Sc) and time t are presented in Figure 11. From this figure it is seen that the concentration decreases with increase in Sc while it increases with time t. Figure 12 reveals the rate of heat transfer coefficient in terms of Nusselt number for different values of radiation parameter R, Prandtl number Pr and Dufour number Dr respectively. It is observed that Nusselt number increases with increasing values of R or Pr but decreases as Du increases. Finally, from Figure 13 it is seen that Sherwood number increases with increase of Sc.

REFERENCES

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Nomenclature

    Absorption coefficient

    External magnetic field

    Species concentration

   Concentration of the plate

   Concentration of the fluid far away from the plate

     Dimensionless concentration

   Specific heat at constant pressure

    Concentration susceptibility

     Acceleration due to gravity

    Thermal Grashof number

    Mass Grashof number

    Magnetic field parameter

    Nusselt number

     Prandtl number

     Radiative heat flux in the y-direction

    Coefficient of mass diffusivity

    Radiative parameter

     Schmidt number

    Temperature of the fluid near the plate

    Temperature of the plate

    Temperature of the fluid far away from the plate

     Time

      Dimensionless time

     Velocity of the fluid in the -direction

    Velocity of the plate

     Dimensionless velocity

    Co-ordinate axis normal to the plate

    Dimensionless co-ordinate axis normal to the plate

Greek Symbols

    Thermal conductivity of the fluid

   Thermal diffusivity

   Volumetric coefficient of thermal expansion

  Volumetric coefficient of expansion with concentration

μ       Coefficient of viscosity

ν        Kinematic viscosity

r         Density of the fluid

ρ        Electric conductivity

σ        Dimensionless temperature

erf      Error function

erfc     Complementary error function

Subscripts

     Conditions on the wall

      Free stream conditions

NOTES

*Corresponding author.

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