This question pertains to hydraulic calculations at the supply and sprinkler sides of a deluge system:
Our example using rough numbers; the deluge system requires 4,000 gpm based on density requirements through the building. This is the system demand.
Now suppose you have a strong water supply. The water supply actually provides 8,000 gpm based on main capacity testing. This is the system supply.
Now my question is, the pipe is wet up to the deluge valve. There is about 50-feet between the deluge valve and the hazard. It is understood that the system demand is 4,000 gpm, but within the pipe network, is it necessary to size the pipe for a deluge system based on 8,000 gpm on the supply side?
Until the water begins discharging through the deluge nozzles, the 8,000 gpm will be surging through the pipe network to reach the nozzles, correct?
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