head loss calculation-fire hydrant sys

7/21/2019 Head Loss Calculation-fire Hydrant Sys

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PIPE FRICTION CALCULATION

The average velocity v in a pipe is calculated based on the formula [1] and the appropriate units

are indicated in parentheses. (see the last page for a table of all the symbols)

The Reynolds Re number is calculated based on formula [2].

If the Reynolds number is below 2000 than the flow is said to be in a laminar regime. If the

Reynolds number is above 4000 the regime is turbulent. The velocity is usually high enough in

industrial processes to make the flow regime turbulent. The viscosity of many fluids can be

found in the Cameron Hydraulic data book. The viscosity of water at 60F is 1.13 cSt.

If the flow is laminar then the friction parameter f is calculated with the laminar flow equation [3].

If the flow is turbulent then the friction parameter f is calculated based on the Swamee-Jain

equation [4].

In the turbulent flow regime the friction factor f depends on the absolute roughness of the pipe

inner wall. Table 1 provide some values for various materials.

STEEL 0.0018ST.ST. 0.0018

CAST IRON 0.0102

PVC 0.00006

The friction factor DHFP/L is calculated with the Darcy-Weisback equation [5]

g =32.17 ft/s²

The pipe friction loss DHFP is calculated with equation [6]

ε



calculationESTIMATING PIPELINE HEAD LOSS AND PUMP SELECTION Project : CRESCENT BY / INFRASTRUCT

USING DARCY WEISBACH METHOD System : FIRE HYDRAND SYSTEM

INPUT

Liquid type : DATA Water q = flow rate Usgpm (GPM) m³ 180 792.6

D = pipe diameter in (inch) 6 6.165 UPVC CLASS E BS3505

L = pipe length ft (feet) 2600 8530

v velocity ft/s (feet/second)

The average velocity v in the pipe is:

V = 0.4085 Xq / D² = 8.52 Ft / s

μ = viscosity CSt (centistokes) , WATER at 60 °F ν 1.13

The Reynolds Re number is:

Re = 7745.8 x V *D / μ = 359999.74Re^0.9 100155

ε = pipe roughness Ft (feet) 0.00006 PVC STEEL 0.0018

f = friction parameter Non dimensional ST.ST. 0.0018

The friction parameter f is: CAST IRON 0.0102

f = 0.25 / {Log10 (ε /3.7*D + 5.74 / Re^0.9)} ² 0.015232 PVC 0.00006

0.01523

∆HFP / L friction factor (feet of fluid/100 ft) of pipe

g = acceleration due to gravity (32.17 ft/s2) 32.17

The friction factor ∆H FP / L is calculated with the Darcy-Weisback equation

∆HFP / L = 1200 f * V ² / D * 2g 3.34 Ft./100Ft of pipe

The pipe friction loss ∆HFP is:∆HFP = ∆HFP / L * ( L/100) 285.27 Feet

Date : 22/ 02

Prepared By

ε



Project :

System :

A - Table:1 CONVERSION FACTORS FOR HEAD LO

( Ft. ) FLOW (q) c1

hL = head loss Input data ft³ /min 6260

c1=conversion factor for head loss calculation (table1). 0.0311 gal /min 0.0311

f = darcy friction factor from moody curve 0.01523242 m³ /s 8.265x(10)1

L = pipe length (feet) 2600 m 8530.18 q² Lit. /min 22950

q = flowrate gal/min 180 m³ / h 3000 792.60 792.6 628214.76

d = pipe iside diameter ( inch) 150 mm upvc class E 6.165 .

Table:2 CONVERSION FACTORS FOR REYNOLD

To find the friction factor ( f ) from curve , Re & Rr sould be calculated: FLOW (q) c2

Reynolds no. Re = (c2 X q X ρ) / d X µ d X µ ft³ /sec 22700

Relative roughness of the pipe Rr =ε /d 6.782 gal /min 50.6

c2 = conversion factor for reynolds No. calculation 50.6 m³ /s 1273000

ρ = fluid weight density 62.34 Lit. /min 22950

µ = fluid absolute viscosity 1.1

ε = Absolute reoughness values for clean pipe : 0.00006 Table:3 (ε)TYPICAL ABSOLUT ROUGHNESS VAL

Reynolds No.Re

368676.6365

3.686766365

Note:

f =64/Re for laminar flow Re less than 2000

f - for turbulant flow Re greater than 2000 Table:4 DENSITIES AND VISCOOSIT

f = 0.015232Table:5 CONVERSION FACTORS FOR VALVES AND FITTINGS FORMULA

FLOW (q) C3 DIAMETER

ft³ /sec 522 in

gal /min 0.00259 in

m³ /s 8265X(10)7 mm ETHYL ALCOHOL

Lit. /min 22.96 mm

PIPE LOSS CALCULATION

hL = ( c1 X f X L X q² ) / (d)^5

FLUID

ST.ST.

PVC

MATERIAL

R. RoughnessRr =ε /d

ETHAN

PROPANE

BUTANE

WATER

ESTIMATING PIPELINE HEAD LOSS AND PUMP SELECTION

USING DARCY WEISBACH METHOD

CRESCENT BY / INFRASTRUCTURE

FIRE HYDRAND SYSTEM

CAST IRON

f = 0.25 / {Log10 (ε /3.7*D + 5.74 / Re^0.9)} ²

0.0000097

STEEL



For flowrate (q) { gal/min} &water at 60˚F . Data and Factors will be:

section flowrate factor factor density viscosity pip diam. friction pipe rough. pipe L

q c1 c2 ρ µ d f ε L(Ft)

L1 792.6 0.0311 50.6 62.34 1.1 6.165 0.01523 0.00006 8530.18373

L2 0 0.0311 50.6 62.34 1.1 1 0 0.0018 0

L3 0 0.0311 50.6 62.34 1.1 1 0 0.0018 0

L4 0 0.0311 50.6 62.34 1.1 1 0 0.0018 0L5 0 0.0311 50.6 62.34 1.1 1 0 0.0018 0

L6 0 0.0311 50.6 62.34 1.1 1 0 0.0018 0

L7 0 0.0311 50.6 62.34 1.1 1 0 0.0018 0

Pipe Head Loss h L ( Ft ) 8530.18373

B - VALVES AND FITTINGS HEAD LOSS

hLvf = c3 X K Xq²/d 4̂ ( Ft. )

c3 = conversion factor for valve head loos calculation TYPE K

K = valve resistance coefficient Pipe entrance,inward proj. 0.78Pipe entrance, Flush 0.5

1

K a 1.5

PIPE DIA.= 6 Ref. A&B

Type L/d from f T fitting Qty K1…n K1…n =[ f T X (L/d )] x No. of valve or fitting t

8 0.013 11 1.144 Table : 6 f T = turbulant friction factors for a partuc

6 0.013 0 0 Reference: A

35 0.013 0 0 Fitting L/D

340 0.013 2 8.84 Globe Valve 340

600 0.013 0 0 Gate Valve 8

50 0.013 1 0.65 Lift Check Valve 600

20 0.013 0 0 Swing Check Valve 50

400 0.013 1 5.2 Ball Valve 6

30 0.013 4 1.56 Butterfly Valve 35

16 0.013 0 0 Pipe Entrance 0.5

20 0.013 1 0.26 Pipe Exit 1

60 0.013 0 0 Tee Through 20

12 0.013 0 0 Tee- Branch flow 60

17 0.013 0 0 Elbow-90 30

34 0.013 0 0 Elbow -45 16

50 0.013 0 0 Bend r/D=3 12

17.654 Bend r/D=6 17

Bend r/D=12 34

Bend r/D=20 50

Pipe Exit , all

globe valve

Bend r/D=3

Check valve , lift

Check valve , swing

Check valve , tilting disc

Ccheck valve , stop check

Gate valve

Ball valve

Butterfly valve

Tee, flow through run

Tee, flow through branch

Bend r/D=6

Bend r/D=12

Bend r/D=20

K b fittings

Elbow-45

K FOR FITTINGS AND VALVES TYPE :

L/d for valves and fittings type :

f T = turbulant friction factors for a partucular pipe diam.

K = f T X (L/d)

Elbow -90

http://f/FAISAL%20RAI/CALCULATIONS..FILES/water.%20pumps%20calculations/pumps%20&%20head%20loos%20calc/REF.PIPE.FLOW.jpg

http://f/FAISAL%20RAI/CALCULATIONS..FILES/water.%20pumps%20calculations/pumps%20&%20head%20loos%20calc/R.ROUGHNESS.bmp

http://f/FAISAL%20RAI/CALCULATIONS..FILES/water.%20pumps%20calculations/pumps%20&%20head%20loos%20calc/R.ROUGHNESS.bmp




Equip. Qty. kc kc

CHIL. COIL 0 11 0

AHU COIL 0 0

H.Exch. 0 0

0

0

0

Equip.kc = 0 c3 K

0.00259 19.154 62

K = Ka+(K1 + K2 + K3 …+Kn )+kc for valves + fittings & Equipment

19.154

C Bernoulli theorem

( pressure head and velocity head )

H = total head

Z = elevation above a reference level

p = pressure

v = mean velocity of the fluid in the pipeline

g = gravitional constat ( 32.2 ft/sec²) US units.

306.63 Ft.

Differintial pressure calculation

(Δp) = p1-p2 = ρ /144 { Z2 - Z1 + (v2² - v1² ) / 2g + h L}

IF NO CHANGE IN PIPE SIZE , ,THE VELOSITY DROPS = 0

0 15.81 Ft. 4.82 m

ρ /144 h L Z2 - Z1 (Δp) PSI Δp Ft Mtr Bar

0.432916667 306.63 15.81 139.58983 322.45 96.74 9.63

Δh Ft fluid = 2.31 p (psi) / SG

h L ( Ft. )

21.57

h L ( Ft. )

Pipe Head Loss

(v2² - v1² ) / 2g

Pipe disch. Elev.(Z2)Pipe inlet Elivation (Z1)

PIPE LINE ,VALVES & FITTINGS

Total head loss in the pipe line (h L)

H = Z+[144 X P / ρ] + [ V² / (2 X g)]

TOTAL PRESSURE LOSS

Equipment kc

K = Ka + Kb + Kc

kc for Equipment

285.06

0

TOTAL VALVES & FITTINGS H

valves & fittings Head Loss



D

HEAD ( TDH ) = Static head (Hs) + friction head (Hf) + pressure hesd ( Hp) + velocity head(Hv)

Static head ( Hs) = is measured from the surface of the liquid in the section vessel to the surface

of the liquid in the vessel where the liquid is being delivered. In closed-loop system , the total static head = 0 .

Fittings & valves Friction head Hf = K X V² / 2g 21.57Pipe Friction head ( From friction loss chart ) Hf = f X L /100 285.06

Velocity head Hv = V² / 2g 0

f = friction ft/ 100 ft 0.01523242 Static Head 15.81

K = resistance coefficient 19.154 322.44

V = Fluid velocity ft/sec. 8.52

g = acceleration due gravity = 32.2 ft./sec² 32.2 Mtr 96.73

Result PSI 139.58

BAR 9.63

Design velocity = ( 4 - 6 ) ft / sec for section

= ( 6 - 8 ) ft / sec for discharge

1 PUMP Horsepower and efficiency:

water horsepower ( WHP ) = Outpot of the pump handlind a liquid

WHP = (Q X H X sg) / 3960

2 Brake horsepower ( BHP ) = Actual supplied power from motor

BHP = ( Q X H X sg ) / 3960 X ή = WHP / ή

ή = pump efficiency

3 Electric current for sizing starters and wire ( I ) [ Amp.]

I = 746 X BHP / 1.73 X E X PF X Eff for 3 ph

I = 746 X BHP / E X PF X Eff for 1 ph

E = Voltage ( volts) 380

PF = Power Factor 0.85

EFF. = Motor efficiency 0.75

1.73 242.25

419.09

Q ( GPM) H (Ft.) SG WHP BHP I ( AMP.)

792.6 322.44 1 64.54 86.05 153.17

94.65 HP

100 HP

PUMP SELECTION AND SIZING

TOTAL DH ( Ft )

PUMP BRAKE HORSPOWER BHP WILL BE +10% =



Q (m3/s) H ( m )

0.0500 98.31

ID = inch m

6.165 0.156591

f L ( m ) V ( m /s ) D ( m ) g

0.015232422 2600.67 2.5972044 0.156591 9.81

93.48

hz hf hp H ( m )

4.82 93.48 0.00 98.31

Q ( m³ /s ) 0.0500

W ( Kg/m3) 1000

H ( m ) 98.31

Eff. 0.75

65.54

HP / 0.75 = 87.38

HP kw

87.38 65.19

96.12

WHP = Q X W X H / 75 =

hf = 4f X L x V² / 2Dg =

TOTAL PUMPING HEAD

OTHER METHOD





f = .005 ( 1 + 1 / 40 D ) ; D = Mtr.



Relative roughness for some common materials can be found in the table below :

x 10-

m feet

Copper, Lead, Brass, Aluminum (new) 0.001 - 0.002 3.33 - 6.7 10-6

PVC and Plastic Pipes 0.0015 - 0.007 0.5 - 2.33 10-5

Epoxy, Vinyl Ester and Isophthalic pipe 0.005 1.7 10-5

Stainless steel 0.015 5 10-5

Steel commercial pipe 0.045 - 0.09 1.5 - 3 10-4

Stretched steel 0.015 5 10-5

Weld steel 0.045 1.5 10-4

Galvanized steel 0.15 5 10-4

Rusted steel (corrosion) 0.15 - 4 5 - 133 10-4

New cast iron 0.25 - 0.8 8 - 27 10-4

Worn cast iron 0.8 - 1.5 2.7 - 5 10-3

Rusty cast iron 1.5 - 2.5 5 - 8.3 10-3

Sheet or asphalted cast iron 0.01 - 0.015 3.33 - 5 10-5

Smoothed cement 0.3 1 10-3

Ordinary concrete 0.3 - 1 1 - 3.33 10-3

Coarse concrete 0.3 - 5 1 - 16.7 10-3

Well planed wood 0.18 - 0.9 6 - 30 10-4

Ordinary wood 5 16.7 10-3

Surface

Roughness - k



0



HEAD ( H ) = Static head (Hs) + friction head (Hf) + pressure head ( Hp) + velocity head(Hv)

Static head ( Hs) = is measured from the surface of the liquid in the section

vessel to the surface of the liquid in the vessel where the liquid is being delivered.In closed-loop system , the total static head = 0 .other equesions :

Fittings & valves Friction head Hf = K X V² / 2g

Pipe Friction head ( From friction loss chart ) Hf = f X L /100

Velocity head Hv = V² / 2g

f = friction ft/ 100 ft

K = resistance coefficient

V = Fluid velocity ft/sec.= V= 0.4085 * q / d² 8.52

g = acceleration due gravity = 32.2 ft./sec²

Design velocity = ( 4 - 6 ) ft / sec for section

= ( 6 - 8 ) ft / sec for discharge

SUMMERY HEAD LOOS

PRESSURE HEAD LOOS DUE TO PIPE FRICTION

SECTION FLOW DIAM. VELOSITY f ( Hfp/L ) L Hfp

GPM in ft/s ft/100 ft pipe ft ft fluid

L1 792.6024 6.165 8.52 3.34 8530.184 285.271

0 #DIV/0! 0 0 0.000

#DIV/0! 0 0 0.000

#DIV/0! 0.000

#DIV/0! 0.000

#DIV/0! 0.000

#DIV/0! 0.000

#DIV/0! 0.000

#DIV/0! 0.000

#DIV/0! 0.000

#DIV/0! 0.000

#DIV/0! 0.000 m

SUBTOTAL 8530.184 285.271 86.97

Z1 = 0 Z2 = 15.81

Static head ΔELIV. Z2 - Z1 15.81

HEAD LOOS & PUMP SELECTION AND SIZING

Hfp=L x f /100



TYPE SECTION FLOW QTY DIA. VEL. v² /2g k ΔHfF

GPM in ft/s ft fluid ft fluid

ENTRANCE 792.6024 1 16 8.52 1.13 1 1.13BUTTERFLY 0 0 16 8.52 1.13 1 1.13

ELBOW 792.6024 6 16 8.52 1.13 0.28 0.32

TEE 90 0 1 16 0.00 0.00 0.7 0.00

GATE VALVE 792.6024 2 16 8.52 1.13 8 9.03

BALL VALVE 0 0 16 8.52 1.13 0.00

GLOB VALVE 0 0 16 0.00 0.00 0.00

1 5 8.52 1.13 1 1.13

1 5 0.00 0.00

1 5 0.00 0.00

1 5 0.00 0.00

ΔHfF ( ft fluid )= k x V²(ft/s)² / 2 x 32.2 (ft/s²) 12.73

PRESSURE LOOS DUE TO EQUIPMENT

SECTION FLOW TYPE QTY ΔP SG ΔP Δh equip

GPM in PSI Ft fluid ft fluid

250 filter 0 0.00 0.98 0.00 0.00

250 H. EXCH 0 0.00 0.98 0.00 0.00250 Cont.valve 0 0.00 0.98 0.00 0.00

0.00

0.00

0.00

0.00

Δh Ft fluid = 2.31 p (psi) / SG

SUMMERY

PIPE Hf = f X L /100 285.27

FITTINGS Hf = K X V² / 2g 12.73

EQUIP.. Δh equip 0.00

VEL.HEAD Hv = V² / 2g 3.70Static Head Hs 15.81 m

TOTAL HEAD LOOS 317.50 96.8001552

PSI 137.44784

SUB TOTAL

PRESSURE HEAD LOOS DUE TO FITTINGS

SUB TOTAL



HEAD LOOS & PUMP SELECTION AND SIZING

1 Horsepower and efficiency:

water horsepower ( WHP ) = Outpot of the pump handlind a liquid

2 Brake horsepower ( BHP ) = Actual supplied power from motor BHP = ( Q X H X sg ) / 3960 X ή = WHP / ή

ή = pump efficiency

3 Electric current for sizing starters and wire ( I ) [ Amp.]

I = 746 X BHP / 1.73 X E X PF X Eff for 3 ph

I = 746 X BHP / E X PF X Eff for 1 ph

E = Voltage ( volts) 380

PF = Power Factor 0.85

EFF. = Motor efficien 0.75

1.73 242.25

419.0925

Q ( GPM) H (Ft.) SG WHP BHP I ( AMP.)

792.6024 317.50 1 63.549199 84.73227 150.8265

93

WHP = (Q X H X sg) / 3960



The Friction Coefficient - λ The flow is

The Fr ic t ion Coeff ic ient for Laminar Flow laminar when Re < 2300

λ= 64 / Re (7) transient when 2300 < Re < 4000

The Fr ic t ion Coeff ic ient for Turbulent Flow turbulent when Re > 4000

λ = f( Re, k / d h )k = relative roughness of tube or duc t wall (mm, ft)

k / d h = the roughness rat io

Relative roughness for materials are determined by experiments.

Relative roughness for some common materials can be found in the table below :

x 10-3

m feet

Copper, Lead, Brass, Aluminum (new) 0.001 - 0.002 3.33 - 6.7 10-6

PVC and Plastic Pipes 0.0015 - 0.007 0.5 - 2.33 10-5

Epoxy, Vinyl Ester and Isophthalic pipe 0.005 1.7 10-5

Stainless steel 0.015 5 10-5

Steel commercial pipe 0.045 - 0.09 1.5 - 3 10-4

Stretched steel 0.015 5 10-5

Weld steel 0.045 1.5 10-4

Galvanized steel 0.15 5 10-4

Rusted steel (corrosion) 0.15 - 4 5 - 133 10-4

New cast iron 0.25 - 0.8 8 - 27 10-4

Worn cast iron 0.8 - 1.5 2.7 - 5 10-3

Rusty cast iron 1.5 - 2.5 5 - 8.3 10-3

Sheet or asphalted cast iron 0.01 - 0.015 3.33 - 5 10-5

Smoothed cement 0.3 1 10-3

Ordinary concrete 0.3 - 1 1 - 3.33 10-3

Coarse concrete 0.3 - 5 1 - 16.7 10-3

Well planed wood 0.18 - 0.9 6 - 30 10-4

Ordinary wood 5 16.7 10-3

The friction coefficient - λ - can be calculated by the Colebrooke Equation:

1 / λ1/2

= -2,0 log 10 [ (2,51 / (Re λ1/2 )) + (k / d h ) / 3,72 ] (9)

Roughness Ratio - k / d h .

Surface

Roughness - k

http://www.engineeringtoolbox.com/colebrook-equation-d_1031.html

http://www.engineeringtoolbox.com/colebrook-equation-d_1031.html

head loss calculation-fire hydrant sys

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