Discharge Capacity Check

7/29/2019 Discharge Capacity Check

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Using Darcy-Weisbach

2

2 5

8f

l

Q L Kh

g D D

5 48 f

lg h

QL K

D D

fl m i n o r h h h

42

28

Dg

QKh

minor

8

ff

h

g


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4

2

2 5

L Q

D

The friction factor

If Q is known assassume rough pipe l

Use Darcy Weisb

Solve for Q or D

Calculate Re andFind new f on Mo

Iterate


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doesnt vary greatly

me f is 0.02, if D is knownwch and minor loss equations

/Ddy diagram

1 3 . 72 lo g

f

D


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DATA INPUT

Kb

0

o

rad 0.131 x q

0.660

Weir 0 903.29 0 0.00 0.00000

0+100 10.00 676.73 16.00 0.28 0.05645

0+200 12.00 676.46 8.00 0.14 0.03572

0+300 24.00 676.19 42.00 0.73 0.10672

0+400 6.40 675.92 36.00 0.63 0.09640

0+500 5.00 675.65 53.00 0.93 0.12443

0+600 7.40 892.06 53.00 0.93 0.12443

Total Length 2435.06 0.54415

Total Kb = 0.54

Select Entrance type Perpendicular square Entrance

Entrance Loss, Ki = 0.5

Select Outlet Type Submerge outlet

Outlet Loss, Ko = 1

Losses due to sudden contractions

D1/D2 1.0 1.5 2.0 2.5

Kc 0 0.25 0.35 0.40

Where D1/D2 is the ratio of the larger diameter to that of the smaller diameter

If D1/D2 is not found in the table

By interpolation

D1 = 1.86

D2 = 1.86

D1/D2 Kc

Higher value 1.5 0.25

Your value 1 0

Lower value 1 0

D1 = 1.86

D2 = 1.86

D1/D2 Kc

Higher value 1.5 0.25

Your value 1 0

Lower value 1 0

Sudden Contraction

Loss, Kc = 0

Losses through fully opened valves

Select Type of Valve GATE

Kv = 0.1

Total Value of K = 2.14

Minor Headloss Coefficient Computation

Point Location Elevation

Deflection angle

Pipe length


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SOURCE OF INFORMATION

"Study of Bend Losses in Large Pipes" (SML)

From AWWA M11 Manual:

Inlet losses

Perpendicular square Entrance 0.5

Inward Projecting Inlet 0.8

Slightly Rounded 0.2

Bell Mouth Inlet 0.1

Outlet loss

Submerge outlet 1 `

Drop outlet 0

Losses through fully opened valves

TYPE Kv

SPHERICAL 0

GATE 0.1

BUTTERFLY

(t/D = 0.2) 0.3


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Inputs: Source of Information:

Diameter 1.61 m

Water Level at Desander 903.29 mASL

Headrace Pipe Top Elevation 892.06 mASL

Pipe Length, L 2,435.06 m

Headloss 11.23 mGravitational acceleration, g 9.810 m

2/s

Pipe Centerline at Surgetank 889.833 mASL

Pipe submergence 1.48 m

Calculation:

A.1 Assume Turbulent flow, compute for f:

Pipe Roughness, 2.5000 mm

Friction factor, f 0.1286 m

Minor Headloss Coefficient, K 14.45

(K/D4) 2.15 m 3.40

(fL/D5) 28.95 m 7.8273562

Actual Headloss, Hlactual 11.23 m 11.229981

Discharge Capacity 2.090530876 m3/s

Velocity 1.026868786 m/s

A.2 Compute final friction factor using initial diameter:

Kenimatic Viscocity 0.000001007 m2/s

Reynolds Number 1,641,766.38

Type of Flow Turbulent

New Friction Factor 0.021977844

A.3 Recompute final diameter using new friction factor:

(fL/D5) 4.95 m

Dischargecap 4.38 m

Velocity, V 2.149426576 m/s

Pipe Roughness, 0.0025 m

Pipe Length, L 2,435.06 m

Minor Headloss, hm 3.40 m

Friction Headloss, hf 7.83 m

Friction Loss, Hlactual 11.23 m

Reynolds Number, Re 3,433,455.37

Friction Factor, f 0.02202

Discharge Capacity 4.37 m3/s

Velocity, V 2.15 m/s

Checking Swamee-Jain Limits:

Check: /D 0.001552795 >> OK 10-6

> OK 5000


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From To From ToBrass and Glass pipe 0.009 0.013 0.009 0.011

Asbestos-cement pipe 0.010 0.012

Wrought-iron and weleded steel pipe 0.010 0.014 0.011 0.013

Wood stave pipe 0.010 0.014 0.011 0.013

Clean cast-iron pipe 0.010 0.015 0.011 0.013

Concrete pipe 0.010 17.000

very smooth 0.011 0.012

"wet mix", steel forms 0.012 0.014

"dry mix", rough forms 0.015 0.016

with rough joints 0.016 0.017

Common-clay drainage tile 0.011 0.017 0.012 0.014

Vitrified sewer pipe 0.010 0.017 0.013 0.015

Riveted-steel pipe 0.013 0.017 0.015 0.017

Dirty or tuberculated cast-iron pipe 0.015 0.035

Corrugated-iron pipe 0.020 0.022

pg 199.., HYDRAULICS By H.W. King, C.O. Wisler, J.G. Woodburn

Viscocity T

Type of channel and description Min. Normal Max. T

A. Closed conduits flowing partly full 0

A-1. Metal 5

a. Brass, smooth 0.009 0.010 0.013 10

b. Steel 15

1. Lockbar and welded 0.010 0.012 0.014 20

2. Riveted and spiral 0.013 0.016 0.017 25c. Cast-iron 30

1. Coated 0.010 0.013 0.014 35

2. Uncoated 0.011 0.014 0.016 40

d. Wrought iron 45

1. Black 0.012 0.014 0.015 50

2. Galvanized 0.013 0.016 0.017 55

e. Corrugated metal 60

1. Subdrain 0.017 0.019 0.021 65

2. Strom drain 0.021 0.010 0.030 70

75

80

8590

95

100

References

Grade Input Values

Values ofn to Be used with the Manning Formula

Values of the Roughness Coefficient, n (Chow, 1959)

Kind of PipeVariation Use in Designing


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ASTM Material Designation Grade Minimum

Yield

Strength

ksi (MPa)

Minimum

Tensile

Strength

ksi (MPa)

A139 B 35 (242) 60 (415) B

C 42 (290) 60 (415) C

D 46 (315) 60 (415) D

E 52 (360) 66 (455) E

55

A36/A36M 36 (248) 58 (400) 60

A516/A516M 55 30 (205) 55 (380) 65

60 32 (220) 60 (415) 70

65 35 (240) 65 (450)

70 38 (260) 70 (485)

Steel Sheet (Flat Coil)

Steel Plate


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Moody Diagram

able

kinematic viscosity (m2/s)

0.000001792

0.000001519

0.000001308

0.000001141

0.000001007

0.0000008970.000000804

0.000000727

0.000000661

0.000000605

0.000000556

0.000000513

0.000000477

0.000000444

0.000000415

0.00000039

0.000000367

0.0000003470.000000328

0.000000311

0.000000296


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Discharge Capacity Check

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