×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Gas flow rate calculation

Gas flow rate calculation

Gas flow rate calculation

(OP)
I am trying to do a calculation....

I have a gas line 10mm and approx 100m long. The pressure in the line is 7 bar when the outlet is closed and is maintained at 7 bar by the supply gas system (gas bottles) when the outlet is open.

How do I calculate the flow rate when the outlet is fully open at the end?

RE: Gas flow rate calculation

You need to know 2 of 3 basic parameters for pipe flow work.
1) inlet pressure
2) outlet pressure
3) flowrate

From your description I think you're saying that the inlet pressure is maintained at 7 bar (but I don't know if its absoute pressure or gage pressure) and the outlet is maintained at atmospheric pressure.  I'll assume pressures are in BarG and make that 7 and 0.

Now see the tutorial on gas flow equations,
http://www.psig.org/papers/2000/0112.pdf

And check your answer here,
http://www.lmnoeng.com/DarcyWeisbach.htm
Note the 40% pressure drop limitation.
 

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Gas flow rate calculation

Remp,

What BigInch has stated is correct.

You may also use the Renouard equation:

pi^2 – po^2 = 46742*rho*L*Q^1.82*D^(-4.82)
 
where:
pi = pressure on the start of pipe line in bar
po = pressure on the end of pipe line in bar
rho = relative density
L = length in km
Q = flow rate in m3/h
D = pipe diameter in mm
 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources