diverging tee friction losses

[lizking]

Are ther any good references for friction loss coefficients for reducing tees, diverging flow? e.g. tee with 10" run, 6" branch: what is loss from 10" to 6" at various flowrate splits?

 

[pleckner]

The conservative approach is to treat the reducing tee as a combination reducer and the lesser diameter tee. The total 'K' value will be 'K' through the reducer (10" x 6") + the 'K' through the 6" tee; branch or run which ever fits your system. You can get the "k" values from CRANE TP410, or better yet, use Hooper 2-K Method.

 

[katmar]

I don't have any definitive data for this set-up and I would follow the same procedure that was recommended by pleckner. One observation I would make is that the pressure drop through a conically tapered reducer, or through a properly formed pipe reducer is very small. Hooper is the only reference I can think of off the top of my head that actually gives data for pipe reducers, even though they are used so much more frequently than conical reducers.

In this case I would probably model the reducer as a sudden reduction from 10" to 6", but this is a rather conservative assumption. I would follow the sudden reduction with a 6" tee exactly as advised by pleckner.

It all depends on how accurate you need to be. If this is one of many fittings in a long line then a high degree of accuracy is probably not required.

Katmar Software
Engineering & Risk Analysis Software

http://katmarsoftware.com

 

[lizking]

Thanks for your responses. I know that a certain large chemical company, D----t, uses loss coefficients from "Internal Flow- A Guide to Losses in Pipe and Duct Systems"' 1971, British Hydromechanics Research Ass'n. and there's a book titled "Handbook of Hydraulic Resistance" by I.E. Idelchik that provides similar info based on area and flow ratios of the various Tee legs. I was hoping that someone knew of a more accessible and commonly accepted source.

 

[pleckner]

The technique I presented is the more commonly used method for reducing (or enlarging) tees.