坝下涵管水力计算wsg(水库放水洞管流量计算)

坝下涵管水力计算

1、无压流坝下涵管的水力计算

Q=ωC(Ri)^0.5经验公式

Q圆涵Dhh/D

C*i^0.5*0.347d^2.50.250.18750.75

0.035606364查得

Kr圆Kω圆

0.6320.302

则

RnCω

0.03950.07550.01446.43689

下泄流量为

Q

0.035638

圆函的直径计算

d=(n*Q/(0.284*i^0.5))^(3/8)

2、有压流坝下涵管的水力计算

Q=μcω（2gH）^0.5

Q

0.080451μc查Q方涵C*i^0.5*0.411当涵洞中水深ω方涵0.75bhR0.33i0.005ω0.99Q1.8034831.966439406218.86487.8ω0.063762H17.80.6D0.2850.2850.285

3、有压渠（路）下涵的水力计算

（1）自由出流

Q=μω（2g（H0+iL-βd）)^0.5

μ=1/(1+∑ζ+2gL/C^2R)^0.5

Qμc

0.0681460.32465n0.014L39.5β=0.85D0.2ω0.0314x0.628R0.05

（2）淹没出流

Q=μHω（2g（H0+iL-ht）)^0.5

μH=1/(ζ出+∑ζ+2gL/C^2R)^0.5

ht-以出口洞底为标高的出口水位

ζ出-涵洞断面面积与出口尾水渠断面积比值选取

μc

0.561635

Q

0.093505

μc

0.401357n0.017L34D0.35ω0.0961625x1.099R0.0875n0.009L30D0.25ω0.049063x0.785R0.0625C69.99561388

Q

0.175298μc

0.05103610.449113

方涵

0.411b^2.5

中水深为洞高的75%

R方涵

0.3b

nCI0.01748.899390.00512000.005CHI43.3544452.250.005063

HI

0.50.01

CHI39.1939550.50.025b1.10.5875hQ矩形涵0.336*i^0.当涵洞ω方涵0.75bhω0.99Q1.803483n（糙率）砼管钢管1.2

Q矩形涵

*i^0.5*b^(8/3)/n

当涵洞中水深为洞高的75%

R方涵

0.3b

RnC0.330.01748.89939Q=ωC(Ri)^0.5

1.80200442

矩形函的宽度计算

d=(n*Q/(0.366*i^0.5))^(3/8)0.014

0.012Ib0.0051.1h1.2n（糙率）