Using the Appropriate Numerical Model

The numerical model should take into account the following assumptions  

In response, the model should be able to draw the theoretical curve which fits the experimental data better, and give the diffusion parameters obtained for this fitting, the diffusivity and the coefficient of convection, as well as the error coefficient evaluating the accuracy of these values as high as possible. 

Full line experimental S-shaped curve with R = 10 D = 10 cm /s L = 0.1 cm. Dotted line curve, with infinite R L = 0.1 cm D = 0.73 x 10 cm /s. Straight line (full line), tangent to the experimental curve with D = 0.92 x 10 cm /s. 

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