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Cliff Dredge
June 14, 2016, 02:24 PM
Hi there, I'm trying to determine a general friction/flow coefficient for a standard stand pipe.291 I 've tried the suppliers and they don't seem to have (or want to pass on) the data. Anyone have any info? Thanks!

Cliff Dredge.

Patrick Moore
June 23, 2016, 01:40 PM
Cliff,

Manufacturers are general the best place for this information as these types of characteristics are specific to their particular model.

One thing You might consider is to use the emitter coefficient methodology discussed in detail in this thread http://forums.innovyze.com/threads/334-Node-emitters-H2OWater if you are trying to model flow out of this specific stand pipe. As far as the specific loss in the stand pipe itself just include the length and potentially minor loss values to account for the bends and losses through the valve mechanism.

Hope this helps

Pat Moore

One last thought: If there are national standards that they hydrant is governed by those can often give you a sense of the maximum headloss requirements at a specific flow that certain items must satisfy. For instance in the US the American Water Works Association typically has a standard that says a typical fire hydrant should have no more than 5 psi headloss through the hydrant when flowing at 1000 gpm. If in Australia there are similar governing requirements those may give you additional information that could be helpful.