${\Vert {\text{Error}}_{\text{ch}}\Vert }_{\infty }$

$\epsilon =10$

${\Vert {\text{Error}}_{\text{ch}}\Vert }_{\infty }$

$\epsilon =1$

${\Vert {\text{Error}}_{\text{ch}}\Vert }_{\infty }$

$\epsilon =\frac{1}{10}$

${\Vert {\text{Error}}_{\text{ch}}\Vert }_{\infty }$

$\epsilon =\frac{1}{100}$

${\Vert {\text{Error}}_{\text{ch}}\Vert }_{\infty }$

$\epsilon =\frac{1}{200}$

$N_x=N_y=21$

1.26E−09

1.12E−10

6.66E−12

3.63E−05

0.004378

$N_x=N_y=41$

1.22E−08

1.77E−09

1.22E−10

1.46E−11

4.93E−09

$N_x=N_y=51$

5.72E−08

4.54E−09

4.76E−10

4.06E−11

1.51E−11

$N_x=N_y=81$

5.04E−07

5.04E−08

3.83E−09

3.73E−10

2.54E−10

$N_x=N_y=101$

1.76E−06

1.53E−07

1.46E−08

9.47E−10

5.89E−10