How does WaterCAD/GEMS determine the age of the tanks using the LIFO or 2-compartment method?

  Product(s): WaterGEMS, WaterCAD, HAMMER
  Version(s): 08.XX.XX.XX
  Area: General

Problem

How does WaterCAD/GEMS determine the age of the tanks using the last in first out (LIFO) or 2-compartment method? What does the "age (calculated)" represent?
(where in the tank is the reported age of the water calculated at?)

Problem ID#: 79740

Solution

The calculated age reported in WaterCAD/GEMS for a tank using the LIFO mixing method is the age at the inlet of the tank.

With the 2 compartment mixing model, the first compartment is considered to have the tank inlet/outlet and is considered fully mixed. The second compartment is considered to be isolated from the first compartment (e.g., dead zone in the tank) and is also considered to be fully mixed.

The second compartment is not "activated" unless there is sufficient volume in the tank and it effectively handles "over-flow" from the first compartment. The reported tank quality (age, constituent, trace) is the average (mixed) value of the first compartment only. The first compartment value is used since this is the compartment that outflow comes from.

See Also

Which "Tank Mixing Model" attribute should I use?

Anonymous
Recommended
Related