Particle setting in a batch reactor

Consider an unstirred batch reactor. The reactor is in the shape of a right circular cylinder with a vertical axis. The volume is $V=30L$ and the height is $H=70cm.$ The reactor is filled with water. Suspended in the water are particles of two sizes. The initial condition $($at time $t=0)$ has all of the particles of each size uniformly suspended throughout the reactor. For $t>0,$ the particles settle to the bottom of the reactor with their respective settling velocities. The data in the following table define the particles in the system.

$\backslash$table$[[$Symbol ${?}^{**},$Parameter,Particle size $1,$Particle size $2],[d_p,$Particle diameter,$5m,10m$