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Hydrant Flow Calculations

Hydrant Flow Calculations provides calculated flow for a set pressure, printable fireflow graphs and hydrant reports.
 
Pipe2012: KYPipe allows fire flow calculations to be made at hydrants, junctions or both. Therefore it is not necessary to include hydrants in your model to calculate fire flows. However, incorporating hydrants in a KYPipe model will allow the user to add additional capabilities to plot hydrant test data, calculate fire flows, and maintain accurate detailed hydrant records. NFPA Hydrant color codes may be applied to emphasize the hydrants. Note: Adding hydrants to your model does not increase the number of pipes (some software would add 2 pipes for each hydrant).

Users can select one or more hydrants for fire flow simulation and receive calculated flow information for a variety of conditions. Some of these conditions include: pumped fire flow limit to maintain specified pressure throughout distribution system, free flow (through hydrant nozzle into atmosphere) and fire flow through hose and nozzle connected to hydrant. Fire flow results are presented in a printable fire flow graph or in a detailed hydrant report.
 
Hydrant Flow-Pressure Data Hydrant Information Maintained by the Model
The hydrant flow results will appear next to each hydrant for which an analysis was conducted.
Hydrant Analysis

Hydrant Data Details
Fireflow Graph
 
Hydrant Test Graph Example

AWWA and NFPA guidelines are used to compute the curve for available pressure as a function of flowrate using the hydrant test data as shown below.
Hydrant Test Graph
 
>"Default Hydrant and Hose Constant / Suction Pressure at Fire Pump Calculation"

A second optional calculation for Hydrants can also be performed to determine the maximum flow to maintain an acceptable suction pressure at the fire pump. The conventional fire flow analysis determines how much flow can be pumped out of the system and not lower the pressure in the distribution system to < 20 psi (or other specified value). This approach may over-estimate the possible fire flow at locations where there is a large capacity. This is because the conventional analysis sometimes may predict fire flows so large they can't be delivered to the pumper at an acceptable suction pressure (e.g. > 0 psi). The losses through the hydrant and hose to the pumper may be far too large for the predicted fire flow.
Hydrant Hose Constant

When values are entered in the fields highlighted in the image above a second calculation will be activated to calculate the maximum flow to maintain an acceptable suction pressure at the fire pump. When this is lower than the first calculation then the conventional approach has over estimated the potential fire flow and the second flow provides a more realistic calculation of the available fire flow.
 
"Hydrant Monitor Element"
Hydrant Monitor element allows the monitor (nozzle) to operate while connecting a hose to one of the other connections. The Hydrant Monitor may be analyzed with up to three valves open simultaneously. The K values for the Hydrant/Monitor may be set at each individual hydrant using the Node Information Data box. Then the valves that are open may by selected in the Device Data box as shown:
 

Hydrant Monitor Element

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