Shape factor FM 3-0 (p.21), NFPA 13 fig. 23.3.2(b) and CEA VdS 4001 Ungleichförmigkeit

[Didi85]

Hi,

im trying to make a comparison between popular Sprinkler Systems in Germany (FM,VdS,NFPA).

My question refers to hydraulic calculations. The water flowrate from one sprinkler is calculated by : Q=k* sqrt(p)*1,4.

In VdS 4001 the factor 1,4 considers that the water flowrate is unequal due pressure lost. And estimate watertank size we use this factor.

NFPA 13 has in 23.3.2(b) a similar factor in its formula : 1.2*sqrt(1500)/13. In this case in the NFPA 13 factor (1,2) the same as in VDS (1.4)

Same with FM3-0 page 21. Its eithre 1.2 oder 1.4 depends on ceilings scope.

I hope you can unterstand what my problem ist

As you may see, im not a native speaker, so i have some trouble to unterstand is correctly.


Thanks in advance