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hamid1 June 7, 2012 06:23

domain length

How much long should be the length of a pipe with velicity inlet/pressure outlet bc?
what about pressure inlet/pressure outlet,
please also consider a body inside the domain

Thank you

delaneyluke June 7, 2012 06:58

If you're asking about the extensions at inlet and outlet then generally use 5D for the inlet extension and 10D for the outlet extension, irrespective of your BC's


hamid1 June 7, 2012 07:26

Thanks for reply,
why these extensions should be added? what if the downstream regime dosnt show any change even after 2D ?

delaneyluke June 7, 2012 08:47

The inlet extension is required so that a fully developed flow enters your pipe domain.
The outlet extension is required to avoid reversed flow at the outlet BC.

You can start with smaller extensions and then increase if the above criteria are not met.


hamid1 June 9, 2012 04:38

thanks for reply

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