**4. Results and Discussions**

In this study, multiple linear regression was used to fit the dimensionless groups equation in order to obtain many empirical coefficients in Equation (13). Comparing the calculated value of the fitted dimensionless groups equation with the water simulation experiment value allowed us to verify the accuracy. The multiple linear regression equation of dimensionless groups can be rewritten into the following mode:

$$\mathrm{lg}\frac{\pi V\_s}{D\_\mathrm{s}} = a\_1 \mathrm{lgCa} + a\_2 \mathrm{lgLa}\_1 + a\_3 \mathrm{lg\delta} + a\_4 \mathrm{lgN}\_{jm} + a\_5 \mathrm{lg}\left(\frac{H\_\mathrm{i}}{H\_{\mathrm{oil}+w}}\right) + a\_6 \mathrm{lg}\left(\frac{h\_\mathrm{s}}{H\_{\mathrm{oil}+w}}\right) \tag{14}$$
