Heat Exchanger Outlets

[786assasin]

Hello,
I have a question if you people can help me. I have two exchangers/ coolers of exactly same dimensions. Its TEMA split flow type. these are copy of each other. each has a duty of 13 mmBtu. but there is a differential in outlets. the difference is that one has 12"outlets that combine in a single 14" spool and then again reduce in a 12"line. while other has both outlets of 12" that remain 12"through out.

both have same quantity of process stream incoming. what do you think what will be effect of having this configuration.


Regards,

 

[IRstuff]

To the first order, wouldn't the former look like a 27% shorter version of the latter?

TTFN

FAQ731-376

 

[whammett]

Yes, a configuration like that will not affect the incoming process stream. And there would be practically no affect. It opens, reducing velocity, and then reduces 2 inches in diameter increasing the velocity of the fluid again, but only back to the velocity it was flowing before..

------ --^--
------ has the same exit velocity as --_--

Sorry for the crude drawing, hope it gets the point across.

The only difference is that it could possibly turn laminar flow into turbulent flow, if the flow wasnt already turbulent to begin with.

"Scientists dream about doing great things. Engineers do them." -James Michener

 

[rmw]

You will have some expansion loss as it transitions from 12" to 14" and some entrance losses as it transitions back. Depending on what your flows are, that difference might be in the second or third decimal place.

I'd want to make sure that the one that had the 14" piece was the one located closer to the rising sun so that the Coriolis force could help equalize the difference. (see tongue in cheek) :=)

rmw