Good Afternoon
Re the Online Pressure Drop and flow rate calculator
Just need some guidance to navigate around this most useful tool
My usual scenarios/requirements are to:
1) Calculate flow from a hydrant or other fitting (hose/tap etc) x metres from a gravity supply tower knowing the head (top water level from ground) pipe material, pipe length and pipe diameter. (which may or may not alter between tower and final flow point) - FLOW Q REQUIRED see example 1 below
2) Calculate static pressure at hydrant assuming flow at Hydrant is known- PRESSURE P2 REQUIRED see example 2 below
3) The same but with a direct pumped system and no break tank
Example 1:
Flow at Hydrant or fitting Required ? l/s
Gravity Head at Tower: 35M (3.5Bar)
Length from tower to hydrant/fitting: 400 M
Pipe Diameter: 200mm for 100 M then 100mm for 300M
Material: Cast Iron – all pipe-work
Example 2:
Pressure at Hydrant/Fitting Needed ? Bar
Flow at Hydrant/Fitting: 5 Lit/s
Gravity Head at Tower: 35M (3.5Bar)
Length from tower to hydrant/fitting: 400 M
Pipe Diameter 200mm for 100 M then 100mm for 300M
Material Cast Iron: – all pipe-work
Most grateful for your guide
Pressure Drop and flow Simple Flow and Pressure Calculations
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Re: Pressure Drop and flow Simple Flow and Pressure Calculat
I think most of your questions can be solved using pressure drop calculator.
Here is report for 100 mm 300 m long pipe
Pipe pressure drop calculator
1. volume flow rate (q):
q : 26.829168 l/s
3. pipe length (L):
L : 300 m
4. pipe diameter (D):
D : 100 mm
6. density (ρ):
ρ : 1000 kg/m3
7. kinematic viscosity (ν):
ν : 1.006 mm2/s
10. velocity (V):
V : 3.4159958 m/s
12. friction coefficient (f):
f : 0.01961603
13. Reynolds number (Re):
Re : 339562.2
15. pressure on the pipe start (p1):
p1 : 45 mWS
16. pressure on the pipe end (p2):
p2 : 10.0 mWS
17. pressure drop (p1-p2):
p1-p2 : 35 mWS
This calculations is assuming that you have constant diameter from start to end. As you said that diameter is changing you should calculate for each segment of pipe but this calculator is not enabled for it.
This is also the case with your second example.
Here is report for 100 mm 300 m long pipe
Pipe pressure drop calculator
1. volume flow rate (q):
q : 26.829168 l/s
3. pipe length (L):
L : 300 m
4. pipe diameter (D):
D : 100 mm
6. density (ρ):
ρ : 1000 kg/m3
7. kinematic viscosity (ν):
ν : 1.006 mm2/s
10. velocity (V):
V : 3.4159958 m/s
12. friction coefficient (f):
f : 0.01961603
13. Reynolds number (Re):
Re : 339562.2
15. pressure on the pipe start (p1):
p1 : 45 mWS
16. pressure on the pipe end (p2):
p2 : 10.0 mWS
17. pressure drop (p1-p2):
p1-p2 : 35 mWS
This calculations is assuming that you have constant diameter from start to end. As you said that diameter is changing you should calculate for each segment of pipe but this calculator is not enabled for it.
This is also the case with your second example.
Pipe flow calculations - free fluid flow calculators
Re: Pressure Drop and flow Simple Flow and Pressure Calculat
Hi, how can I increase the pressure, of air flow through a pipe, from 6 Pa to around 1500 Pa? Thank you.
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Re: Pressure Drop and flow Simple Flow and Pressure Calculat
You can either use ventilator or increase pipe diameter to reduce pressure drop but it should be checked
Pipe flow calculations - free fluid flow calculators
Re: Pressure Drop and flow Simple Flow and Pressure Calculat
Liked the thread.. I think pressure drop calculator is an effective instrument for air pressure measurement.
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Re: Pressure Drop and flow Simple Flow and Pressure Calculat
Yes, you should use pressure drop calculator.