A reciprocating compressor produces 10tons of refrigeration at an evaporator temperature of 50C and a condenser temperature of 350C. Estimate how much cooling effect it can produce at an evaporator temperature of - 300C, the condenser temperature remaining un-altered.
Given: Refrigerant: R-12, clearance = 5%, index of compression (in both cases) is 1.15. Extract from refrigerant property tables:
|
Temp
|
Pressure (bar)
|
Specific volume
$\left ( m^{3}/kg \right )$
|
Enthalpy (kJ/kg)
|
|
|
|
Liquid ´ 103
|
vapour
|
Liquid
|
vapour
|
|
-30$^{\circ}$c
|
1.005
|
0.672
|
0.1600
|
8.88
|
174.96
|
|
+5$^{\circ}$c
|
3.631
|
0.725
|
0.0478
|
40.81
|
190.88
|
|
+35$^{\circ}$c
|
8.501
|
0.787
|
0.0208
|
69.74
|
202.96
|