Branch Piping Turbulence

[boze]

Need some opinions on the following flow situation, which I believe will cost many dollars and not provide significant results.

Have a request to determine flow disturbance created by modifying an existing piping system.

Turbulent flow (water at std conditions) in 8' diameter pipe.
Install 24" diameter branch with blind flange for access.
Fabricate a 24" flange connection with an internal plug to fill the short branch volume. The plug face will match the existing 8' diameter wall contour. Claim is to mitigate additional turbulence. Line pressure is 40 psi, Reynolds number in the 1*10^7 range(upper end of transition phase).
Cannot believe that the disturbance (turbulence) is significant when the plug will conform to the large pipe ID.

Connection will be several diameters downstream of a normally full open check valve, so the flow regime profile will not be fully developed.

Yes there will be a small gap at the interface, but certainly no redirection of the flow.

My comments to date - FEA and /or CFD would be the only way to go, and the results would be insignificant. Losses are minimal for a normal "tee" connection without a plug or branch flow.

Believe that determining the flow conditions at the plug insert would require a total analysis of the pipe upstream and downstream, supports, check valve, vibration etc. in order to get meaningful relative data. Cost could be significant.

Tis a puzzle that I have not had to address during 30 years of piping, except head box piping (cotton test) in Paper Mills.

 

[BRIS]

Why ?

These sort of solutions I have had to adopt in high velocity reservoir outlets to avoid cavitation damage but to adopt such a solution to reduce, what is likely to be a negligible head loss, as you say will spend dollars with no result.

Is there any other reason such as a downstream flow meter installation?

 

[MJCronin]

bose,

I agree with BRIS...... Why ?

I also agree with you in your statement: "Losses are minimal for a normal "tee" connection without a plug or branch flow."

I do not understand why you must "determine flow disturbance" for these modest flow and pressure conditions.

Is flow induced corrosion a concern ? Is raw water being used and corrosion may be a concern ?

If so, thicken the pipe and tee and dont worry about it.

I have seen hundreds of piping systems modified repeatedly in more radical ways than you describe with no ill effects...

My opinion only

-MJC