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niceguy514
Feb 21, 2007, 10:31 AM
I am making a heat exchanger as a project so I am going to ask a whole bunch of questions at once.

The system will consist of a pump, evaporator and condenser. The cold side will have a temperature of anything below 0 C and the high side will have anything higher then 2 C.

I want to use R134 which evaporates at -26 C at 101kPa.

If I vacuumed the system, the pressure should correlate with the Temperature. But now since I have 2 temperatures, what would the saturation temperature be. I got stuck here because I would not be able to calculate the heat transfer coefficient.

If I were to pressurize the system to 293kpa, which will mean a saturation temperature of 0. If the temperature reaches 20 C. Does this mean that it would be Psat + Initial Pressure.

Last question but not the least :) .

Will this system always be at film boiling and film condensation?

rahul_chaubey
May 2, 2007, 08:17 AM
Hi
This s rahul
I thnk I could be able to answer your quistion
But your question is not clear
If u want to design heat exchanger, you need to take various parameters into consideration
1. no of tubes
2 thermal conductivity of material being used
3 Tonnage of compressor
Reagrds
Rahul

awnshaikh
Jul 16, 2007, 05:37 AM
Dear Niceguy514

Could you clarify that you want to design heat exchanger or the whole system?