Modeling Fire water system with EPAnet

[chung4382]

Hello,

It is my first time using EPAnet to model a fire water system. I am modeling 6 hydrants flowing simultaneously at a demand of 9,000 (1,500 per hydrant). I am wondering if i need to set a base demand (1,500 gpm) at each hydrant as well as a set a emitter coefficent? Or is this just unnecessarly increasing my demand at each hydrant? I am using a emitter coefficient of 150 gpm/psi^.05. Thanks in advance.

 

[hydrae]

The emitter coefficient is additive to the base demand
you should not need it in your model.
The theoretical 1500 gpm is adjusted in the real world for higher or lower pressure by the fire fighters, so if you have extra pressure the fire fighters will not open the valve as wide or run their pumper truck as hard.

If you are wanting to know what the flow would be out of the hydrants if they were all wide open, that is where the emitter coefficient comes in, then you would set the base flow to zero and adjust the coefficients until you got the 9000 gpm total demand


Hydrae