In order to ascertain discharging capacities for fire extinguishing purpose of the municipal water supplying nets, we performed 2 experiments besides one preliminary at one section of Kanamachi Katsushika-Ku, Tokyo.
Experiments were made to ascertain natural hose discharging and pump discharging capacities under the case of (1) single pipe line, (2) nets lines. We have computed the discharging amount of Qc from the total friction loss of lines by using Darcy’s formula for old cast iron pipe, and compared with the values Qo measured from experiments.
In these experiments mercury manometer was used at the coupling between hose and nozzle for the accurate measurement of Qo.
We have found that in the 1st experiment the value mean of Qo/Qc is 0.31 and the 2nd is 0.40, that is the discharging capacity is about 30~40% of that for the case of cast iron pipe where Darcy’s formula was applied.