//Chapter-6, Illustration 9, Page 316 //Title: Refrigeration cycles //============================================================================= clc clear //INPUT DATA T2=40;//Temperature at point 2 in oC T1=-5;//Temperature at point 1 in oC h2=367.155;//Enthalpy at point 2 from F-12 tables in kJ/kg sg=1.55717;//Entropy from F-12 tables in kJ/kg-K s1=1.54057;//Entropy at point 1 from F-12 tables in kJ/kg-K sf=0.98311;//Entropy from F-12 tables in kJ/kg-K hf=195.394;//Enthalpy from F-12 tables in kJ/kg hfg=153.934;//Enthalpy from F-12 tables in kJ/kg h4=238.533;//Enthalpy at point 4 from F-12 tables in kJ/kg h4s=218;//Enthalpy at point 4 with subcooling from F-12 tables in kJ/kg //CALCULATIONS x1=(s1-sf)/(sg-sf);//Quality factor h1=hf+(x1*hfg);//Enthalpy at point 1 from refrigerant-12 tables in kJ/kg COPns=(h1-h4)/(h2-h1);//Co-efficient of performance with no subcooling COPs=(h1-h4s)/(h2-h1);//Co-efficient of performance with subcooling //OUTPUT mprintf('COP with no subcooling is %3.3f \n COP with subcooling is %3.3f',COPns,COPs) //==============================END OF PROGRAM=================================