Figure 3.

Isotherms of iteration method I (the first line), iteration method II (the second line) and iteration method III (the third line) with different viscosity coefficients $1.0$ (the first column), $1.0\times {10}^{-3}$ (the second column) and $1.0\times {10}^{-4}$ (the third column). $D_a=1$, ${\beta }_T=1$, ${\beta }_C=1$, $\gamma =0.1$, $D_c=0.01$.