Project : AGRICULTURE BANK AL EHSAA

HYDRAULIC CALCULATION

FOR

CHILLED WATER PUMPS

TOTAL DYNAMIC HEAD

SUPPLIER

LAMAH EST.P.O. BOX : 4814 RIYADH 11412 KSA

TEL: 01- 4915826 FAX : 01- 4915927

Project : AGRICULTURE BANK AL E HASSA

0

Head loss calculation using ( 1 ) COLBROOK Formula For CHILLED WATER PUMPS

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Local factors of fittings

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Lin

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no. DN mm m mm GPM l/s 0.2

0.2

8.0

2.0

0.2

0.3

0.9

0.5

2.0

1.0 1/1 m m/s 1/1 1/1 m m m m m

A - B 4" GI 102 1 0.1 340 21.4 1 1 1 1 1 5.4 2.60806 266700.48 0.02061 6.99 0.07 1.872 1.94 1.94

B - C 4" GI 102 4 0.1 340 21.4 2 1 1.1 2.60806 266700.48 0.02061 6.99 0.28 0.381 0.66 0.66

C - G 6" GI 154 18 0.1 680 42.8 3 2.7 2.29756 354008.19 0.01882 3.29 0.59 0.726 1.32 1.32

G - I 3" GI 77.92 21 0.1 155 9.77 2 1 1 2 2.04779 159563.45 0.02233 6.13 1.29 0.427 1.71 1.71

I - J 1 1/4" GI 35.08 6 0.1 25 1.58 2 1 1.1 1.62956 57165.116 0.02802 10.8 0.65 0.149 0.8 0.8

J - K 1 1/4" GI 35.08 20.5 0.1 25 1.58 1 0.3 1.62956 57165.116 0.02802 10.8 2.22 0.041 2.26 2.26

K - L 1 1/4" GI 35.08 10.2 0.1 25 1.58 1 0.9 1.62956 57165.116 0.02802 10.8 1.1 0.122 1.22 1.22

L - FCU 1/2" GI 15.76 17 0.1 4 0.25 1 1 1 1 11.4 1.29181 20358.906 0.03621 19.5 3.32 0.97 4.29 4.29

TOTAL 98 0 0 1 0 0 7 6 4 1 0 0 10 5 14 14.21

Pressure drop in chiller = 10.00 m

Pressure drop in FCU = 1.32 m

two way valve loss = 1.00 m

total friction loss = 14.21 m

Total dynamic head supply = 26.53 m

Total dynamic head return = 26.53 m

Safty factor 20% = 10.61 m

total dynamic head = 63.66 m

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Vel

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1.942

2.603

3.921

5.635

6.432

8.689

9.914

14.21

14.21

CHILLED WATER PUMPS

Project : AGRICULTURE BANK AL Page ( 1 )

Head Loss Calculations:

The total friction loss Hs Consist of:

Hs = Hs1 + Hs2 …………………………………………………….…… (1)

Where: Hs1 : Friction loss Inside pipesHs2 : Friction loss inside fittings

Linear friction loss equation:

Hs = J . L …………………………………… ……………………………………... .... (2)

Where: J : linear loss factorL : length Of the pipe (m.)

: friction loss factor (COLBROOK-WHITE formula)V : velocity of water (m/s)g : gravity acceleration (9.81 m/s²)D : pipe inside diameter (m.)

COLBROOK WHITE formula:……………………………………………………………….. ( 4 )

1 = - 2 x log [

k+

2.51)

3.7 x D

Where: K : pipe inside Surface roughness (m.)D : pipe inside diameter (m.)

RE : REYNOLD’S no. is given as follows: (1/1)

Where: n 1E-06V : velocity of water (m/s)D : pipe inside diameter (m.)

V = Q / A ………………………………………...………………………………………. ( 6 )

Where: Q : flow rate (m³/s)A : cross section are of the pipe (m²)

Data for the first pipe : 4" GI Pipe type & size 4"

114.3 mm Out side diameter (mm)6.02 mm Wall thickness (mm)

D = 0.10226 m : pipe inside diameter (m.)K = 0.0001 m : pipe inside Surface roughness (m.)

J = l . V² / ( 2 g D ) ………..…………………………………………………………….. (3)

l

sqr(l) Re x sqr( l )

RE = V x D / n …………………………………………………………………………. ( 5 )

: water viscosity= ( n = m2/s)

Project : AGRICULTURE BANK AL EHSAA Page ( 2 )

Flow : Q = 340.0 GPM = 21.42 l/s = 0.02142 m³/sec

A = 3.14 x 0.102 ² / 4 = 0.00821 m²

V = Q / A = 2.608 m/s

2.608 x 0.1023 / 0.000001 = 266700.48

1 = - 2 log [

0.0001+

2.51 ]

3.7 x 0.102 266700.5

By solving above equation :

0.02061

0.02061 x 2.6081 x 2.608= 0.06988 m/m 2 x 9.81 x 0.1023

Loss m per 100 m = J x 100 = 0.06988 x 100 m = 6.988 m / 100m

Pipe length L = 1.0 m

dh(1) Liner loss = J x L = 0.06988 x 1.0 = 0.07 m

Local losses equation is given as follows:

HS2 = SUM ZE . V ² / ( 2 . G ) …..…………………………………………………….. (7)

Where: G : Gravity acceleration (9.81 m/s²)V : Velocity of water (m/s)

SUM ZE : Sum of local loss factors

SUM ZE = gate valve 1 x 0.2 = 0.2Flexible 0 x 0.2 = 0Globe valve 0 x 8 = 0check valve 1 x 2 = 2elbow ( 45 leg.) 0 x 0.2 = 0elbow ( 90 leg.) 1 x 0.3 = 0.3tee 1 x 0.9 = 0.9reducer 0 x 0.5 = 0Strainer 1 x 2 = 2discharge outlet 0 x 1 = 0Total local factors = 5.40

HS2 = SUM ZE . V ² / ( 2 . g )

HS(2) = SUM ZE.x V² / ( 2 g ) = 5.4 x 2.6081 X 2.6081

= 1.8721 m 2 x 9.81

DH Total loss = HS1 + HS2 = 0.07 + 1.872 = 1.942 m

p x D2 / 4 =

Re = V x D / n =

sqr(l) x sqr( l )

l =

J = l . V² / ( 2 g D ) =

Total heal (DH+GH) / pipe = Static head + Friction losses ………………………. ( 8 )

= 0.0 + 1.942 = 1.942 m

Project : AGRICULTURE BANK AL EHSAA Page ( 3 )

Data for the second pipe : 4" GI Pipe type & size 4"

114.3 mm Out side diameter (mm)

6.02 mm Wall thickness (mm)

D = 0.10226 m : pipe inside diameter (m.)K = 0.0001 m : pipe inside Surface roughness (m.)

Flow : Q = 340.0 GPM = 21.42 l/s = 0.02142 m³/sec

A = 3.14 x 0.102 ² / 4 = 0.00821 m²

V = Q / A = 2.608 m/s

2.608 x 0.1023 / 0.000001 = 266700.48

1 = - 2 log [

0.0001+

2.51 ]

3.7 x 0.102 266700.5

By solving above equation : 0.02061

0.02061 x 2.6081 x 2.608= 0.06988 m/m 2 x 9.81 x 0.1023

Loss m per 100 m = J x 100 = 0.06988 x 100 m = 6.988 m / 100m

Pipe length L = 4.0 m

dh(1) Liner loss = J x L = 0.06988 x 4.0 = 0.28 m

Local losses equation is given as follows:

HS2 = SUM ZE . V ² / ( 2 . G )

SUM ZE = gate valve 0 x 0.2 = 0Flexible 0 x 0.2 = 0Globe valve 0 x 8 = 0check valve 0 x 2 = 0elbow ( 45 leg.) 0 x 0.2 = 0elbow ( 90 leg.) 2 x 0.3 = 0.6tee 0 x 0.9 = 0reducer 1 x 0.5 = 0.5Strainer 0 x 2 = 0discharge outlet 0 x 1 = 0Total local factors = 1.10

HS2 = SUM ZE . V ² / ( 2 . g )

HS(2) = SUM ZE.x V² / ( 2 g ) = 1.1 x 2.6081 X 2.6081

= 0.3814 m 2 x 9.81

DH Total loss = HS1 + HS2 = 0.28 + 0.381 = 0.661 m

Total heal (DH+GH) / pipe = Static head + Friction losses

p x D2 / 4 =

Re = V x D / n =

sqr(l) x sqr( l )

l =

J = l . V² / ( 2 g D ) =

= 0.0 + 0.661 = 0.661 m

Total Head for pipe 1 & 2 = 1.942 + 0.661 = 2.603 m

Other pipes are calculated same as above, All data and results are arranged in the following table :