NPSH Calculator Author: Dimitrii Pokrovskii
[email protected] www.engineering-bear.com
www.azpiping.com
Nov. 16th, 2007, Brought to you by
with permittance from Author
1 - Start
2
Pump Operating Parameters
System Inlet Height Configur Open System:
Fluid Temperature (through the pump): Total Pump Volumetric Flow Rate:
(32 - 212 F)
Atmospheroc Pressure:
(can't change)
Fluid Vapor Pressure:
45 deg. F 0 gpm 14.7 PSI 33.96 ft. Water 0.75 (ft. Water)
Surface Pressure 0
Water Vapor Pressure Reference Table Water Temp. Vapor Pressure (Deg. F) (ft. Water) 80 1 100 2 120 4 140 7 180 18 200 28 212 33.96
liquid level
Water Vapor Pres. @ Sea Level
Vapor Pres.(ft. Water)
35 30 25 20 15 10 5 0 75
100
125
150
175
Temperature Deg. F
liquid level
200
225
Each sub system is defined by a fitting that either changes the pipe size or a Tee that combines or separates flow.
from Author
2
3-
Inlet Height Configuration
System Piping Configuration 1 Pipe Type
Schedule 40 1 0 0
Pipe Size (Nominal) Pipe Length Flow Rate (Positive) Height h
Fittings 90 Ells 45 Ell Globe Valve Angle Valve Ball Valve BF-Valve Ck-Valve Stand. Tee - flow through run Stand. Tee - flow through branch -
inlet Surface Pressure PSIG inlet -h (Negative) Height
4 Height:
Static Head 0 ft.
Qt.
(Optional) Pipe Type Pipe Size (Nominal) Pipe Length Flow Rate
Fittings Qt. 90 Ells 45 Ell Globe Valve Angle Valve Ball Valve BF-Valve Ck-Valve Stand. Tee - flow through run Stand. Tee - flow through branch -
Eq. Length 0 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 Total Eq. Length
Schedule 40 1 0 0
Eq. Length 0 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 Total Eq. Length
Design Calculator - Do not Edit Values Here
Total Fitting Eq. L NA NA NA NA Ref. NA NA NA NA NA 1 4 2 5 3 6
Nominal Diam.
Pipe Length (ft.) NA NA NA NA NA NA NA NA NA 0 0 0 0 0 0
0 0 0 0 0 0
1 2 3 4 5 6 8 10 12 14 1 1 1 1 1 1
ID (inch) 1.05 2.07 3.07 4.03 5.05 6.07 8.07 10.14 12.09 13.13 1.049 1.049 1.049 1.049 1.049 1.049
3 - When You're Done W/ Step 3 - Press the Calculate NPSH Button 2 inch ft gpm
Total
Fittings Qt. 90 Ells 45 Ell Globe Valve Angle Valve Ball Valve BF-Valve Ck-Valve Stand. Tee - flow through run Stand. Tee - flow through branch -
0 0 0 0 0 0 0 0 0 0 0
5 inch ft gpm
Total 0 0 0 0 0 0 0 0 0 0 0
(Optional) Pipe Type Pipe Size (Nominal) Pipe Length Flow Rate
(Optional) Pipe Type Pipe Size (Nominal) Pipe Length Flow Rate
Fittings Qt. 90 Ells 45 Ell Globe Valve Angle Valve Ball Valve BF-Valve Ck-Valve Stand. Tee - flow through run Stand. Tee - flow through branch -
Schedule 40 1 inch 0 ft 0 gpm
Eq. Length 0 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 Total Eq. Length
Total 0 0 0 0 0 0 0 0 0 0 0
Schedule 40 1 inch 0 ft 0 gpm
Eq. Length 0 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 Total Eq. Length
Total 0 0 0 0 0 0 0 0 0 0 0
Rel. Roughness e=
Pipe ID Area (inch^2) Flow GPM 0.86 NA 3.36 NA 7.39 NA 12.73 NA 20.01 NA 28.89 NA 51.16 NA 80.69 NA 114.8 NA 135.3 NA 0.86 0.86 0.86 0.86 0.86 0.86
Flow (ft^3/s) Velocity (ft/s) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0
Re
Friction Factor 0 NA 0 NA 0 NA 0 NA 0 NA 0 NA 0 NA 0 NA 0 NA 0 0 0.0009533 0.01 0.0009533 0.01 0.0009533 0.01 0.0009533 0.01 0.0009533 0.01 0.00095329 0.01 Total Frictional Head L
e/D
0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
0 0 0 0 0 0 0 0 0
0.000 0.000 0.000 0.000 0.000 0.000
0 0 0 0 0 0
ate NPSH Button 3
(Optional) Pipe Type Pipe Size (Nominal) Pipe Length Flow Rate
Schedule 40 1 inch 0 ft 0 gpm
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 branch0 60 0 0 Total Eq. Length
6
(Optional) Pipe Type Pipe Size (Nominal) Pipe Length Flow Rate
Total 0 0 0 0 0 0 0 0 0 0 0
Schedule 40 1 inch 0 ft 0 gpm
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 branch0 60 0 0 Total Eq. Length
Total 0 0 0 0 0 0 0 0 0 0 0
Safety Factor Piping Fittings
HEAD Fittings NA NA NA NA NA NA NA NA NA NA
1.3 1.3 HEAD LOSS
Head Pipe NA NA NA NA NA NA NA NA NA NA
0 0 0 0 0 0 0 0 0 0 0 0 Total Frictional Head Loss:
Sum NA NA NA NA NA NA NA NA NA NA 0 0 0 0 0 0 ft. water 0 PSI 0
13769344.xls
Date: Job Name: Drawings / Page: Max GPM:
NPSH Calculation
1/31/2009 7:28
Address:
Constants / Assumptions: Mean Operating Fluid Temperature:
45 ºF
Total Flow Through Pump:
0 gpm
Pumped Fluid: WATER
Vapor Pressure of Liquid:
0.75 ft. water
Atmospheric Pressure:
14.70 PSIA
33.96 ft. Water
Surface Pressure:
0 PSIG
(if exposed to air surface pressure = 0)
Piping Configuration: Pipe Sub System#: Pipe Diam. (Nom): Pipe Length: Flow Rate:
1
2
1 inch 0 feet 0 gpm
Pipe Pressure Drop: 0.0 ft. Water 0.0 psi Valves (Fully Open) / Fittings
Qt. 90 Ells 45 Ell Globe Valve Angle Valve Ball Valve BF-Valve Ck-Valve Stand. Tee - flow through run Stand. Tee - flow through branch Eq. Length Total:
0 0 0 0 0 0 0 0 0 0
1 Eq. Length Total 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 0 0
Fitting Pressure Drop: 0.0 ft. water 0.0 psi
Additonal Pressure Drops:
3
4
5
6
1 inch 0 feet 0 gpm
1 inch 0 feet 0 gpm
1 inch 0 feet 0 gpm
1 inch 0 feet 0 gpm
1 inch 0 feet 0 gpm
0.0 ft. Water 0.0 psi
0.0 ft. Water 0.0 psi
0.0 ft. Water 0.0 psi
0.0 ft. Water 0.0 psi
0.0 ft. Water 0.0 psi
Qt. 0 0 0 0 0 0 0 0 0 0
2 Eq. Length Total 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 0 0
0.0 ft. water 0.0 psi
Qt. 0 0 0 0 0 0 0 0 0 0
3 Eq. Length Total 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 0 0
0.0 ft. water 0.0 psi
Description input here input here input here input here input here Total:
0.0 0.0 0.0 0.0 0.0 0.0
Qt. 0 0 0 0 0 0 0 0 0 0
4 Eq. Length Total 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 0 0
Qt. 0 0 0 0 0 0 0 0 0 0
0.0 ft. water 0.0 psi
5 Eq. Length Total 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 0 0
0.0 ft. water 0.0 psi
ft. water ft. water ft. water ft. water ft. water ft. water
Qt. 0 0 0 0 0 0 0 0 0 0
Total 0.0 0.0
6 Eq. Length Total 20 0 16 0 340 0 150 0 8 0 29.9 0 55 0 20 0 60 0 0 0 0
0.0 ft. water 0.0 psi
Total 0 0.0 0.0
Total Head Loss (Pipe + Fittings + Additional Drops) :
0.0
Results (Static Head)
NPSHA
(Vapor Pressure)
+ + = 34.0 0.0 0.0 (Atmospheric Pressure) (Surface Pressure) Net Positive Suction Head Available Pump Schedule #: MFR: Model #:
0.8
(Loss in Fittings)
-
0.0 (Loss in Pipe Length)
0.0
NPSHA
-
0.0 (Additonal Loss)
=
NPSHR Net Positive Suction Head Required (From Pump Curve)
33.21
ft. Water
0
ft. Water
Safety Factor Enter NPSHR
Air Systems Confidential
01/31/2009
Page 9
PDF Table of Schedule 40 & 80 Pipe Geometry
Adobe Acrobat 7.0 Document
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
Schedule 80
Schedule 40
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 hand looks like there is a safety factor associated with the table values when compared to the theo Pressure Drop in 100 ft. of Pipe My Value Flow Wheel DI GPM 1.85 2.4 3 100 1.5 1.95 3 90 0.92 1.2 3 70 0.68 0.9 3 60 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
Rel. Roughtness e = 0.001 Ratio 1.0 Rel. Roughness e = 0.001 Ration 1.3
2.75
ASHRAE Value
2.5 2.25 2 1.75 1.5 1.25 1
1.2 1.4 1.6 1.8
2
My Value
2.2 2.4 2.6 2.8
ASHRAE Value
re to the table values found in the handbook and the pump wheel table values when compared to the theoretical values. More testing needs to be done with a wider range of flows and pipe sizes 2.5 2.25 2 1.75 1.5 1.25 1 0.75 0.6
0.8
1
1.2
1.4
My Value
1.6
1.8
2
e of flows and pipe sizes
ASI-NPSH Calculator VS HVAC PUMP Handbook
1000 1500 2000 2250 2500 2750 3000 3250 3500 3750 4000 4250 4500 4750 5000 5250 5000
Asi Calculator Head Loss for 100 ft of Pipe (ft of Water)
Handbook Head Loss for 100ft of Pipe (ft of Water)
Flow Rate (GPM)
HVAC PUMP Handbook - Author: James B. Rishel
