New user to EPANET

[cvegan]

Hi,

I'm new to the forum and EPANET as well. I need to do a fire flow analysis for a relatively short line of 8" PVC that will have 2 new fire hydrants connected to an existing system. I don't have static pressure information for the existing hydrant but the residual was measured at 103 psi, and the flow at 826.20 gpm. I am unsure about how to set up the initial conditions (at the existing) in my system, if it should be considered a tank or reservoir, and what inputs I should use to model the fire flow correctly. I will attach what I have thus far, and hopefully someone will have a good idea on how I should proceed. Thank you for your time!! (Sorry, I had to edit the attachment because I noticed the elevations were not added to the junctions.)

 

[Pinwards]

You need the static pressure from the Flow Test to be able to model it. Essentially you will be modeling the existing system using a pump and reservoir to simulate the distribution system that's supplying the water. The pump curve is set using 3 data points: 1. Static Pressure at Q=0; 2. Residual Pressure at Q=Flow Test; and 3. Calculated available fire flow at the minimum allowed pressure (typically 20 psi) calculated as shown here:

http://www.hosemonster.com/blog/calculate-rated-capacity-20-psi/

Without the static pressure, you don't have 1 and can't calculate 3.

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[cvegan]

Thank you for your help!!