Pressure drop through series of holes 1

[mills82]

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!

Andy

 

[Latexman]

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,
Latexman

 

[btrueblood]

Manifold is another search term.

 

[bimr]

Crane Technical Paper No. 410

http://www.flowoffluids.com/publications/crane-tp-410.aspx

 

[davefitz]

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.

 

[btrueblood]

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

 

[btrueblood]

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

 

[mills82]

Thank you all. Very much appreciated!