Proposition of Novel Refrigerants in Various Cooling Devices

Abstract

In context of severe climate change, present dissertation proposes environmentally benign and energy efficient mixed refrigerants working in cryocoolers and air conditioners. The performance of the mixed refrigerants are compared with pure fluid refrigerants and the commercial refrigerants. . Certain nitrogen + hydrocarbon mixtures and nitrogen + carbon dioxide mixture are suggested for cryocoolers and hydrocarbon mixtures and carbon dioxide + isobutane mixure is suggested for air conditioner.
A cryo refrigerator or a cryocooler is used to operate at cryogenic temperature, i.e., below -150 0C. Linde Hampson cryogenic refrigerator is widely used as a cryo refrigerator. Pure fluids are usually used as refrigerant. The operating pressure for pure fluids is very high. It is important to decrease the operating pressure and achieve the same amount of refrigeration.
An air conditioner is a common household appliance. It used R134a coolant which is a hydrofluorocarbon (HFC). HFC’s have high global warming potential. So, it is important to find an environment friendly alternative of R134a. R600a (isobutane) has gained popularity now a days. But, isobutane can’t be used in the operating pressure of the air conditioner because of its phase behaviour constraint.