Schmidt Number

The Schmidt number is calculated using the van Rijn (1984b) formula which is based on measurements from Coleman (1981)

1)	$\begin{array}{l}\displaystyle \frac{1}{\sigma _{sk}}=1+2\left(\frac{\omega _{sk}}{u_{}}\right)^{2}\,\,\,\,\,\mathrm{for}\,\,0.1< \frac{\omega _{sk}}{u_{}}< 1\end{array}$

where

$\begin{array}{l}ω_{sk}\end{array}$ = sediment settling velocity for k^th grain class [L/T]

$\begin{array}{l}u_*\end{array}$ = total bed shear velocity [L/T]

The applying the above equation the values of $\begin{array}{l}ω_{sk}/u_*\end{array}$ values are limited to the range indicated above.