Tutorial for CIVL252 Hydraulics
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Tutorial for CIVL252 Tutorial for CIVL252 Hydraulics Hydraulics By DUAN Huanfeng By DUAN Huanfeng [email protected] [email protected]
description
Tutorial for CIVL252 Hydraulics. By DUAN Huanfeng [email protected]. y0. y1. Example 1. Problem rectangular channel with 6ft width. y0, y1 are 65ft and 1ft, respectively horsepower lost =? in the hydraulic jump. Solution From section 0 to 1 From section 1 to 2 Head loss (Method 1). - PowerPoint PPT Presentation
Transcript of Tutorial for CIVL252 Hydraulics
Tutorial for CIVL252 Tutorial for CIVL252 HydraulicsHydraulics
Tutorial for CIVL252 Tutorial for CIVL252 HydraulicsHydraulics
By DUAN HuanfengBy DUAN [email protected]@ust.hk
Example 1• Problem
– rectangular channel with 6ft width.– y0, y1 are 65ft and 1ft, respectively– horsepower lost =? in the hydraulic jump
y0
y1
• Solution– From section 0 to 1
– From section 1 to 2
– Head loss (Method 1)
11.3y1*g v1/F1
64.2ft/s y1)-(y0*2g v1 0~ v0
(1) /2gv1y1 /2gv0y0 22
15.5ft 1)-8F1(* /2)(y1 y2 21
horsepower 2,150 550 / Hr QP
49.2ft y2) y1 /(4y2) - (y1 H
LLoss
3L
• head loss (Method 2)– For section 1 and 2:– V1=64.2ft/s; y1=1ft;– V2=?; y2=15.5ft;– According to continuity EQ:
• V2=64.2*1/15.5=4.142ft/s
– According to Energy EQ:• HL = (y1+V12/2g) - (y2+V22/2g)=49.2ft
Example 2
• Problem– Water flows at a steady rate of 12 cfs
per foot of width in the wide rectangular concrete channel shown. Pls determine the water surface profile from section 1 to section 2.
1 q=12 cfs/(s*ft)
Slope = 0.04 Rectangular weir
2
3ft
• Solution– First, determine type of the flow regime.Assume n =0.015; the depth is h1.
!sup'
133.3/
/23.16/74.0
)04.0()015.0/49.1(12
/49.1
1
11
21
32
11
21
32
flowercriticalasIt
ghVFr
sfthqVandfth
hh
SARnQ
• Second, determine whether a water jump occurs upstream of the weir.
occurwilljumpwaterhhP
fthComputeP
hKfth
hLhgKQ
firstKAssumeweironOverhead
ftFrhh
hdepthSequent
sw
w
ww
ww
s
s
13.326.5
26.2:Re_
44.005.040.033.2
12.32242.0122
)42.0()2(
13.3)181)(2/(
:)1(
23
23
21
– Furthermore, determine the distance from the weir to where the hydraulic jump occurs.
ftx
x
S
fassumeEQDarcyRgfVS
ftRsftV
sftVsfthqVand
SSgVVhhx
f
avgavgf
averageaverage
s
fss
0.57
)04.0000121.0/(]4.64/)67.467.14()56.513.3[(
000121.0
015.0.).(/8/
34.4;/0.3
/16.2;/83.3/
)/(]2/)()[(
2
11
022
11
• Complete the water surface profile
0.74ft
3.13ft5.26ft
57.0ft
