Vup 
\large
$$
V_{up}  = V_c  \times \left( {1 + {{L_{lamella} } \over {b_{lamella} }} \cdot \cos (\alpha ) \cdot \sin (\alpha )} \right)
$$
Alternative Vup
\large
$$
V_{up}  = {{Q_{{\rm{tank}}} } \over {L \cdot w}}
$$