Pressure Flow
Flow from pressure drop (inverted Hazen-Williams): Q = [ΔP/0.00980665 · C^1.852·D^4.87 / (10.67·L)]^(1/1.852); velocity v = Q/A.
通過水帶入口與出口壓力差,利用哈森-威廉公式反算水帶實際流量與流速,用於現場供水狀態評估與水力校核。