CHAPTER 2:The Refrigeration Cycle¶

EXAMPLE 2.1,PAGE NUMBER:21¶

In [1]:
# Variable Declaration
T_l=0+273;# The required cooling temperature of room in °C
T_h=30+273;# The temperature of outside air in °C
T_e=-5+273;# The evaporating temperature of Refrigeration cycle in °C
T_c=35+273;# The Condensing temperature of Refrigeration cycle in °C
deltaT=5;# The temperature difference at the evaporator and the condenser in K
h_i=249.7;# Enthalpy of fl uid entering evaporator in kJ/kg
h_e=395.6;# Enthalpy of saturated vapour leaving evaporator in kJ/kg
h_sup=422.5;# Enthalpy of superheated vapour leaving compressor in kJ/kg

# Calculation
CarnotCOP=T_l/(T_h-T_l);
print"The Carnot COP for the process is",round(CarnotCOP,1)
# For Refrigeration cycle,
CarnotCOP=T_e/(T_c-T_e);
print"The Carnot COP for the refrigeration cycle is",round(CarnotCOP,1)
# For R134a,
Q=h_e-h_i;# Cooling effect in kJ/kg
W_in=h_sup-h_e;# Compressor energy input in kJ/kg
COP=Q/W_in;# Ideal R134a vapour compression cycle COP
print"The Carnot COP for the ideal vapour compression cycle  is",round(COP,1)

The Carnot COP for the process is 9.0
The Carnot COP for the refrigeration cycle is 6.0
The Carnot COP for the ideal vapour compression cycle  is 5.4