×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

Flow coefficient according to IEC 60534 vs CFD simulation software

Flow coefficient according to IEC 60534 vs CFD simulation software

Flow coefficient according to IEC 60534 vs CFD simulation software

(OP)
Hello every one. I have a problem with flow coefficient of ball and butterfly valve.
I tried to calculate flow coefficient of some butterfly valves according to IEC and simulating the scheme indicated. All values obtained with CFD are very close to real values but other competitors declare almost double values for same valve. I also tried to calculate kv value of ball valve (not far from a pipe with 8 nominal pipe diameters plus face to face length of valve).
Also in this case values obtained with CFD compared to values declared by ball valves manufacturer are very far.
In the simulation I have a 3D pipe with my valve, fluid is water ambient temperature, dP of 1 bar from inlet to outlet and software calculate the volume flow rate. Is there something wrong?

RE: Flow coefficient according to IEC 60534 vs CFD simulation software

Fabiobs,

I have seen similar competitor claims in for choke valve Cv values. In the one specific instance I am thinking of it turned out to be marketing claims for a vapor ware valves that was still under development. It may be the same in your case, but there is always a non zero possibility that you analysis is incorrect. A few questions to ask yourself:

1.) Is there one specific competitor making the claim, or is it every body else.

2.) Has you company ever physically tested a valve that you can use to validate you CFD methodology?

3.) How do the Cv values you generated stack up the the Cv values of an orifice diameter of the equivalent flow area exposed?

You may want to make a more detailed post in the CFD forums to see if it is something on your end. Much like the physical test methods for Cv I would change the flow parameters you are looking at to determine your Cv. If you are only going for a 1 bar dp across the valve you may be in a laminar flow regime. I would run a range of dp's and flow rates to see if you are getting consistent results, and use the average of those values to determine a Cv. At the end of the day you need to validate your CFD method by comparing a physical test to simulation results in order to have confidence in your simulation.

RE: Flow coefficient according to IEC 60534 vs CFD simulation software

(OP)
Thank you for your reply.
I think that all competitors try to declare a higher value than the real one. We had a test bench used to test small valves (up to 1"1/2) and CVs obtained in the test are +/- 4% CVs obtained in CFD analysis.
The problem is that competitors values are nearly twice as much.

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! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close