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View Full Version : NH3 thermosiphon evaporator calculation



cygbob
19-11-2007, 04:37 AM
hi everyone,
I have a nh3 refrigeration project which need to use a thermosiphon evaporator. I made a calculation but I'm not sure with the result.so I need someone can make a check on my calculation.

Qe=2300KW,Te=-38℃,cacl2 brine 29% by wt, -30/-35℃,

the calculation:
area=656m2, ¢20*2, l=8000, number=1310,tube pitch=26, shell id=1010mm, recirculation rate=4,
fouling resistence:shell/tube 0.00017/0.000088 m2.k/W

it's the first time to do this so i need your help.

many thanks!

cygbob

TXiceman
24-11-2007, 06:15 PM
A couple of things, what program did you use to do the calculation and did you allow for any submergence on the evaporator temperature?

Ken

Peter_1
25-11-2007, 01:50 PM
I think we have to speak here of a coil or heat-exchanger instead of an evepoartor.

cygbob
27-11-2007, 11:00 AM
I made the program by myself, the in-tube heat transfer coefficient get by the Gungor and Winterton(1986) equation.
Cacl2 brine is out of the tubes, Ammonia is evaporating in the tube. The recirculation rate=4.
I'm not sure what the 'submergence' means

Thanks,
cygbob