W (MM ) H (MM ) i Q=VA (m 3 /s) v=R 2/3 i 1/2 /n (m/s) A=WH (m 2 ) ρ =2W 2H (m) R=A/ ρ (m) 系数 n= 矩形断面暗渠水力计算(满流) 2200 2200 0.01 24.99 5.16 4.84 8.800 0.550 0.013