Two different cylindrical tanks interconnected by a pipe with a valve.
A mathematical model of the process is required to determine the change in height of the fluid in the 2nd tank when the valve is opened. A system time constant is also required. Attached is an example of Mass Balance for one tank.
Analysis of the flow of liquid through a connected double tank system and derivation of system model to predict height of liquid in second tank at any time and the time constant of the system