We can use the sprinkler nozzle pressure, but as a means to the end of estimating how high the sprinkler will project water:
1. use the nozzle pressure with K-factor to get flow = Q, 2. with Q, divide by sprinkler orifice area (A) to get velocity. This is the max possible velocity as deflector will slow 90% of the spray. 3. from velocity, use Bernoullis at v2= 0 m/s velocity, to predict the height water will rise 4. note, once the water is outside the sprinkler, the pressure is essentially ambient, so P1 ~ P2 in Bernoulli's equation. 5. solve for z, maximum height the water will rise from vertically oriented sprinkler. This seems like a lot of energy and discussion for a relatively minor sprinkler design point. I mean, if we have gotten to the point of a fire where a column sprinkler is to save the structure, perhaps we earlier missed some more important fire protectioin design-issues, at least more important than sidewall horiztonal or sidewall down/up. Do you think sometimes we put more energy into debating the simple points, because they are simpler to think about, and we spend less time debating the not-so-clear subject material, because we don't want to spend the mental energy, even though that is the effort that would yield the-most-design value for the time? Scot Deal Excelsior Fire/Risk Engineering _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
