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MilosBog
14-02-2011, 07:59 PM
Hi all,
as it became so common that i ask some stupid questions here i am once again.
Could anybody tell me is there any recommendation for a refrigerant pressure drop in the condenser and evaporator? What are the common values? I dont need it for a particular project, just for an information and orientation
BR to all

AastroGuru
08-03-2011, 10:30 AM
It depends on the size of the condenser or evaporator.
The smaller the pressure drop, is the better.
Usually it lies in Pascals for smaller condensers/evaporators say around 50000 Pascals for 200 kg/hr.
It will not be in bar or Mpa level. Anything above 0.5 bar is poor design for smaller condensers.

The pressure drop is directly related to design of heat exchanger and mainly due to the losses due to friction and corners/flow path.

Yuri B.
09-03-2011, 04:33 PM
Pressure drop between 2 points of the pipe depends on the flow rate in it.

botrous
09-03-2011, 08:06 PM
Hi Astoguro,
Acceptable pressure drops in Condensers 5 to 15 PSI (refrigerant side)
Acceptable pressure drops in evaporators 2.5 to 10 PSI (refrigerant side)

Please note that the pressure drop across finned tube heat exchangers is directly related to the coil circuiting, the mass flow and the number of feeds.

Best regards

AastroGuru
10-03-2011, 06:18 AM
Thats little over 1 bar for Cond and 0.5 bar for Evap. I agree.
Thanks for the info.

botrous
11-03-2011, 09:14 AM
You are welcome ;)

MilosBog
30-03-2011, 04:33 PM
Thanks guys...I wondered because i have done some calculations in Solkane for a refrigerant cycle because i needed a capacity of the condenser for one building to preselect the pumps and to see is it really worth of doing the Geothermal energy for cooling ad therefore i needed figures...Thanks