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View Full Version : Ambguity in Refrigeration tonnage of Chiller







ioncube
17-06-2015, 06:50 PM
My model is YPC-ST-400 meaning its TonsOfRefrigeration (TR) is 400
As can be seen we have total refrigerant (water) amount of 550kg

http://i59.tinypic.com/2h5mmjb.jpg

Using steam tables at (~5celsius) saturated properties of water:


SATURATED
Sat. pressure 0.8718 kPa ~6.5mmHg
Sat. temperature 5.0000 C
Quality 1.0000
Moisture 0.0000
Enthalpy
hf 21.0067 kJ/kg
hfg 2489.7275 kJ/kg
hg 2510.7342 kJ/kg
Internal energy
uf 21.0058 kJ/kg
ufg 2361.4265 kJ/kg
ug 2382.4323 kJ/kg
Entropy
sf 0.0762 kJ/kg/C
sfg 8.9507 kJ/kg/C
sg 9.0269 kJ/kg/C
Specific volume
vf 0.0010 m3/kg
vfg 147.1621 m3/kg
vg 147.1631 m3/kg

Thus at evaporator per kg water being evaporated @6.5mmHg will remove ~2489.7275kJ
of enthalpy from the chilled water. Assuming that ~60% of 550kg water is continously
circulated to evaporator we can calculate max. amount of enthalpy that is being
removed & then translate it to TR ...1TR=~3.5kW ...1kJ/sec=1kW

TR = 2489.7275kJ/kg x (550x0.6)kg/hr x 1hr/3600sec x 1TR/3.5kW = 65.2TR

Even if I had 100% water circulation to evaporator which is nonsense I cannot get the value 400TR?

Brian_UK
17-06-2015, 11:11 PM
And what is the result when using the LiBr mixture?