NPSH Calculator
Author: Dimitrii PokrovskiiNov. 16th, 2007, Brought to you by
with permittance from Author
1 - Start
2
Pump Operating Parameters
System Inlet Height Configuration
Open System:
Fluid Temperature (through the pump): (32 - 212 F) 45 deg. F
Total Pump Volumetric Flow Rate: 0 gpm
Atmospheroc Pressure: (can't change) 33.96 ft. Water14.7 PSI
Fluid Vapor Pressure: 0.75 (ft. Water)
Surface Pressure
Water Vapor Pressure Reference Table 0
Water Temp. Vapor Pressure (Deg. F) (ft. Water) 80 1 100 2 120 4 140 7 180 18 200 28 212 33.96 [email protected] www.engineering-bear.com
www.azpiping.com
75 100 125 150 175 200 225 0 5 10 15 20 25 30 35Water Vapor Pres. @ Sea Level
Temperature Deg. F V apor P re s .(ft. W ater ) liquid level liquid level
with permittance from Author
2
3 - When You're Done W/ Step 3 - Press the Calculate NPSH Button
System Inlet Height Configuration
System Piping Configuration
1
Pipe Type Schedule 40Pipe Size (Nominal) 1
Pipe Length 0
Flow Rate 0
Fittings Qt. Eq. Length
90 Ells 0 20
45 Ell 0 16
Globe Valve 0 340
Angle Valve 0 150
Surface Pressure Ball Valve 0 8
PSIG BF-Valve 0 29.9
Ck-Valve 0 55
Stand. Tee - flow through run 0 20 Stand. Tee - flow through branch 0 60
- 0 0
Total Eq. Length (Optional)
4
Pipe Type Schedule 40Pipe Size (Nominal) 1
Static Head Pipe Length 0
Height: 0 ft. Flow Rate 0
Fittings Qt. Eq. Length
90 Ells 0 20 45 Ell 0 16 Globe Valve 0 340 Angle Valve 0 150 Ball Valve 0 8 BF-Valve 0 29.9 Ck-Valve 0 55
Stand. Tee - flow through run 0 20 Stand. Tee - flow through branch 0 60
- 0 0
Total Eq. Length
h -h inlet inlet (Positive) Height (Negative) Height
Each sub system is defined by a fitting that either changes the pipe size or a Tee that combines or separates flow.
Design Calculator - Do not Edit Values Here
Pipe Length (ft.) ID (inch)
Ref. NA NA 1 1.05 NA NA 2 2.07 NA NA 3 3.07 NA NA 4 4.03 NA NA 5 5.05 NA NA 6 6.07 NA NA 8 8.07 NA NA 10 10.14 NA NA 12 12.09 14 13.13 1 0 0 1 1.049 4 0 0 1 1.049 2 0 0 1 1.049 5 0 0 1 1.049 3 0 0 1 1.049 6 0 0 1 1.049 Total Fitting
3 - When You're Done W/ Step 3 - Press the Calculate NPSH Button
(Optional)
2
Pipe Type Schedule 40inch Pipe Size (Nominal) 1 inch
ft Pipe Length 0 ft
gpm Flow Rate 0 gpm
Total Fittings Qt. Eq. Length Total
0 90 Ells 0 20 0 0 45 Ell 0 16 0 0 Globe Valve 0 340 0 0 Angle Valve 0 150 0 0 Ball Valve 0 8 0 0 BF-Valve 0 29.9 0 0 Ck-Valve 0 55 0
0 Stand. Tee - flow through run 0 20 0
0 Stand. Tee - flow through branch 0 60 0
0 - 0 0 0
0 Total Eq. Length 0
(Optional)
5
Pipe Type Schedule 40inch Pipe Size (Nominal) 1 inch
ft Pipe Length 0 ft
gpm Flow Rate 0 gpm
Total Fittings Qt. Eq. Length Total
0 90 Ells 0 20 0 0 45 Ell 0 16 0 0 Globe Valve 0 340 0 0 Angle Valve 0 150 0 0 Ball Valve 0 8 0 0 BF-Valve 0 29.9 0 0 Ck-Valve 0 55 0
0 Stand. Tee - flow through run 0 20 0
0 Stand. Tee - flow through branch 0 60 0
0 - 0 0 0
Rel. Roughness
e = 0
Flow GPM Flow (ft^3/s) Velocity (ft/s) Re e/D
0.86 NA 0 0.000 0 0 NA 3.36 NA 0 0.000 0 0 NA 7.39 NA 0 0.000 0 0 NA 12.73 NA 0 0.000 0 0 NA 20.01 NA 0 0.000 0 0 NA 28.89 NA 0 0.000 0 0 NA 51.16 NA 0 0.000 0 0 NA 80.69 NA 0 0.000 0 0 NA 114.8 NA 0 0.000 0 0 NA 135.3 NA 0 0 0 0.86 0 0 0.000 0 0.0009533 0.01 0.86 0 0 0.000 0 0.0009533 0.01 0.86 0 0 0.000 0 0.0009533 0.01 0.86 0 0 0.000 0 0.0009533 0.01 0.86 0 0 0.000 0 0.0009533 0.01 0.86 0 0 0.000 0 0.00095329 0.01
Total Frictional Head Loss: Pipe ID Area
3 - When You're Done W/ Step 3 - Press the Calculate NPSH Button
(Optional)
3
Pipe Type Schedule 40Pipe Size (Nominal) 1 inch
Pipe Length 0 ft
Flow Rate 0 gpm
Fittings Qt. Eq. Length Total
90 Ells 0 20 0 45 Ell 0 16 0 Globe Valve 0 340 0 Angle Valve 0 150 0 Ball Valve 0 8 0 BF-Valve 0 29.9 0 Ck-Valve 0 55 0
Stand. Tee - flow through run 0 20 0 Stand. Tee - flow through branch0 60 0
- 0 0 0
Total Eq. Length 0
(Optional)
6
Pipe Type Schedule 40Pipe Size (Nominal) 1 inch
Pipe Length 0 ft
Flow Rate 0 gpm
Fittings Qt. Eq. Length Total
90 Ells 0 20 0 45 Ell 0 16 0 Globe Valve 0 340 0 Angle Valve 0 150 0 Ball Valve 0 8 0 BF-Valve 0 29.9 0 Ck-Valve 0 55 0
Stand. Tee - flow through run 0 20 0 Stand. Tee - flow through branch0 60 0
- 0 0 0
Safety Factor Piping 1.3 Fittings 1.3 HEAD LOSS Sum NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ft. water
Total Frictional Head Loss: 0 PSI 0
HEAD
13769344.xls
Air Systems Confidential 01/31/2009 Page 9
Date: 1/31/2009 7:28 NPSH Calculation
Job Name: Address:
Drawings / Page: Max GPM:
Constants / Assumptions:
Mean Operating Fluid Temperature: 45 ºF Total Flow Through Pump: 0 gpm Atmospheric Pressure: 14.70 PSIA 33.96 ft. Water
Pumped Fluid: WATER Vapor Pressure of Liquid: 0.75 ft. water Surface Pressure: 0 PSIG (if exposed to air surface pressure = 0)
Piping Configuration:
Pipe
Sub System#: 1 2 3 4 5 6
Pipe Diam. (Nom): 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch
Pipe Length: 0 feet 0 feet 0 feet 0 feet 0 feet 0 feet
Flow Rate: 0 gpm 0 gpm 0 gpm 0 gpm 0 gpm 0 gpm
Total Pipe Pressure Drop: 0.0 ft. Water 0.0 ft. Water 0.0 ft. Water 0.0 ft. Water 0.0 ft. Water 0.0 ft. Water 0.0
0.0 psi 0.0 psi 0.0 psi 0.0 psi 0.0 psi 0.0 psi 0.0
Valves (Fully Open) / Fittings
1 2 3 4 5 6
Qt. Total Qt. Total Qt. Total Qt. Total Qt. Total Qt. Total
90 Ells 0 20 0 0 20 0 0 20 0 0 20 0 0 20 0 0 20 0 45 Ell 0 16 0 0 16 0 0 16 0 0 16 0 0 16 0 0 16 0 Globe Valve 0 340 0 0 340 0 0 340 0 0 340 0 0 340 0 0 340 0 Angle Valve 0 150 0 0 150 0 0 150 0 0 150 0 0 150 0 0 150 0 Ball Valve 0 8 0 0 8 0 0 8 0 0 8 0 0 8 0 0 8 0 BF-Valve 0 29.9 0 0 29.9 0 0 29.9 0 0 29.9 0 0 29.9 0 0 29.9 0 Ck-Valve 0 55 0 0 55 0 0 55 0 0 55 0 0 55 0 0 55 0
Stand. Tee - flow through run 0 20 0 0 20 0 0 20 0 0 20 0 0 20 0 0 20 0
Stand. Tee - flow through branch 0 60 0 0 60 0 0 60 0 0 60 0 0 60 0 0 60 0
- 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Total
Eq. Length Total: 0 0 0 0 0 0 0
Fitting Pressure Drop: 0.0 ft. water 0.0 ft. water 0.0 ft. water 0.0 ft. water 0.0 ft. water 0.0 ft. water 0.0
0.0 psi 0.0 psi 0.0 psi 0.0 psi 0.0 psi 0.0 psi 0.0
Description
Additonal Pressure Drops: input here 0.0 ft. water
input here 0.0 ft. water
input here 0.0 ft. water
input here 0.0 ft. water
input here 0.0 ft. water
Total: 0.0 ft. water Total Head Loss (Pipe + Fittings + Additional Drops) : 0.0
Results
(Static Head) (Vapor Pressure) (Loss in Fittings) NPSHA
NPSHA = 34.0 + 0.0 + 0.0 - 0.8 - 0.0 - 0.0 - 0.0 = 33.21 ft. Water
(Atmospheric Pressure) (Surface Pressure) (Loss in Pipe Length) (Additonal Loss)
Net Positive Suction Head Available
Pump Schedule #: NPSHR 0 ft. Water
MFR: Net Positive Suction Head Required
Model #: (From Pump Curve)
Safety Factor Enter NPSHR Eq.
Nom. Diam. Inchs 1/8 1/4 3/8 1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 3 1/2 4 5 6 8 10 12 14 16 18 20 24 PDF Table of Schedule 40 & 80 Pipe Geometry Adobe Acrobat 7.0 Document
Schedule 40 Schedule 80 ID ID Inches Inches 0.27 0.22 0.36 0.3 0.49 0.42 0.62 0.55 0.82 0.74 1.05 0.96 1.38 1.28 1.61 1.5 2.07 1.94 2.47 2.32 3.07 2.9 3.55 3.36 4.03 3.83 5.05 4.81 6.07 5.76 7.98 7.63 10.02 9.56 11.94 11.38 13.12 12.5 15 14.31 16.87 16.13 18.81 17.94 22.63 21.56
This Data is for Development Purposes
Note: Trying tofigure out how my fluids results compare to the table values found in the handbook and the pump wheel
looks like there is a safety factor associated with the table values when compared to the theoretical values. More testing needs to be done with a wider range of flows and pipe sizes Rel. Roughtness Pressure Drop in 100 ft. of Pipe
e = 0.001 My Value Flow Wheel DI GPM
Ratio 1.0 1.85 2.4 3 100 1.5 1.95 3 90 Rel. Roughness 0.92 1.2 3 70 e = 0.001 0.68 0.9 3 60 Ration 1.3 2.7 2.7 5 400 1.6 1.6 5 300 2.4 2.3 6 700 1.2 1.3 8 900 1.5 1.6 8 1000 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 1.25 1.5 1.75 2 2.25 2.5 2.75 My Value AS H R AE V al u e
Note: Trying tofigure out how my fluids results compare to the table values found in the handbook and the pump wheel
looks like there is a safety factor associated with the table values when compared to the theoretical values. More testing needs to be done with a wider range of flows and pipe sizes
0.6 0.8 1 1.2 1.4 1.6 1.8 2 0.75 1 1.25 1.5 1.75 2 2.25 2.5 My Value A S H R AE V al u e
ASI-NPSH Calculator VS HVAC PUMP Handbook HVAC PUMP Handbook - Author: James B. Rishel
Flow Rate (GPM)
looks like there is a safety factor associated with the table values when compared to the theoretical values. More testing needs to be done with a wider range of flows and pipe sizes 1000 1500 2000 2250 2500 2750 3000 3250 3500 3750 4000 4250 4500 4750 5000 5250 5000
