THERMODYNAMIC ANALYSIS OF AIR REFRIGERATION CYCLE WITH DOUBLE REGENERATION

Abstract

With the growing concern of researchers to achieve low temperature and high COP in conventional refrigeration cycles, lots of modifications has been suggested and successfully implemented in the existing refrigeration cycles except air refrigeration cycle where very few of it is available in literatures. So, in the present study for achieving the given objective a double regenerated air refrigeration cycle is considered .Its thermodynamic analysis is done from the point of view of achieving low temperature refrigeration. The exergy destruction of each of the components in the system is determined. In this arrangement the cold air leaving the refrigerated space is first used to cool the air leaving the compressor. Also some fraction of chilled air leaving the turbine is extracted for further cooling of air leaving the first heat exchanger. A simulation analysis is performed by varying the parameter such as mass extracted, the effectiveness of heat exchangers & pressure ratio to get low temperature refrigeration. The simulation is also carried out by varying above parameters to get exergy destruction of each component in the system using EES. It is investigated that by adding another heat exchanger as a regenerator the cabin temperature decreases considerably but there is a slight decrease in the COP of the cycle compared to the conventional regeneration cycle. The results of simulation are used to study the influence of various operating parameters such as effectiveness of heat exchangers, pressure ratio & percentage of mass extracted low temperature at the exit of turbine in order to get low temperature refrigeration. The results can be useful in the design of heat exchangers as well as control of other thermodynamic parameters to get optimum COP, as well as to get low temperature refrigeration.