Length Distance
Available pressure avail = P_pump − P_nozzle − ρg·Δh (Δh elevation m); friction loss per metre per_m = 10.67·Q^1.852/(C^1.852·D^4.87)×0.00980665; max supply distance L_max = avail/per_m.
根据消防泵出口压力、所需出口压力、地形高差与水带规格,估算单条供水干线能够达到的最大有效供水距离,用于火场供水方案规划。