×
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

Cavitation effects in round edged orifice entrance

Cavitation effects in round edged orifice entrance

Cavitation effects in round edged orifice entrance

(OP)
I have been looking at pressure profiles and cavitational effects through sharp-edged orifice plates. How do these profiles, effects and the mathematical formulas change for round edged orifices? Are there any specific correction factors?

RE: Cavitation effects in round edged orifice entrance

The coefficient of discharge enters in the formula which relates flow rate and pressure drop through an orifice. Since cavitation occurs when liquid pressure drops below its vapour pressure, you can understand the way edge shape affects this issue.

As far as I know the coefficient of discharge is assumed to be 0.6 for sharp-edge and 0.98 for round edge orifice.

The only equation I am aware of for the coefficient of discharge is from ISO 5167 (Stoltz equation) that you can find at the link below.

http://www.lmnoeng.com/orifice.htm#equations

Hope it could help
 

RE: Cavitation effects in round edged orifice entrance

(OP)
How are these correction factors implemented in a formula?
Also, for the first graph, are the x-axis values ratios between orifice length and orifice cross section, or orifice cross section and pipe cross section?

RE: Cavitation effects in round edged orifice entrance

Hi Sykhan88,

Please refer to additional page for orifice plates from Internal Flow Systems by Miller. The X -axis on the first graph is the ratio of the CSA of the orifice divided by the upstream pipe CSA.

The Ko value for a sharp edged is simply multiplied by the correction factor Crad for rounded orifice edges as the pressure loss is less for these types of orifice plates.

Regards

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