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


Pressure drop through series of holes

Pressure drop through series of holes

Pressure drop through series of holes

Good morning,

How can I calculate the pressure drop through a series of drilled holes in a pipe? I need the flow rate from each to be the same and therefore I am thinking that these holes will increase in size along the tube in order for the pressure drop across each to be the same.

I look forward to your responses!


RE: Pressure drop through series of holes

Did you Search (beneath the thread title between Forum and FAQs) this forum for past threads on the subject?  There have been several.  Use keywords like pipe sparger, flow maldistribution, and distributor pipe may get you to some good posts.  If you have any questions after that, please let us know.

Good luck,

RE: Pressure drop through series of holes

Manifold is another search term.

RE: Pressure drop through series of holes

here are some answers I provided in 2007 to a similar question:

here are some references that are useful for determining the flow unbalance in manifolds/ headers ( as I listed in a earlier thread):

Bajura, RA "A model for flow distr...: trans ASME 98-A-4,473-479 Oct 76

Acrivos, A Chem Eng Sci V10 p112 1959

Keffer, JF J Fluid Mech 15 p 481 & , 1963

Bajura, RA, Jones, EH J trans ASME V93 ser A no 1 pp 7-12 Jan 71

Ahn, H KSME Int J 12(1):87-95 feb 98

Hager,WH P I Mech Eng C-J Mech 201(6):439-448 1987

Greskovi, EJ , Obara, J T Ind Eng chem proc DD 7(4):593 1968

A science citation search of newer articles that reference these papers may provide more modern techniques, such as using FLUENT etc 3D CFD to simulate the flow in the headers.

As I recall, some of the older correlations were based on the assumption that the header internal design was formed using "set-thru" tube welds, which led to a higher internal header friction pressure drop then the now normal design of a set-in flush weld of tubes to header.

Another detail to note is that the headers are often drilled with smaller holes than the attached piping, to allow fit-up if a set-on stub weld is used ( ie ASME sect I fig "Z" weld).So, it isnot always corect to assume the header drilled holes equals the attached piping ID.

RE: Pressure drop through series of holes

Great post Dave - lps for that.  Suggest you make it a FAQ.

RE: Pressure drop through series of holes

P.s. - might add bimr's Crane TP410 reference to the list.

RE: Pressure drop through series of holes

Thank you all. Very much appreciated!

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!


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