Performance of a VCR System with Variable Capillary Tube Geometry and R134a Refrigerant Charge Through Forced Convection at Various Air Velocities

Refrigerators are now considered to be the most vital component of modern life.The primary criterion is energy usage because the compressor in refrigerators (vapour compression refrigeration systems) needs fuel to work.The main problems brought in by the over use of fossil fuels are the quick depletion of fossil fuel resources and the environmental contamination.Therefore, a methodical approach is required to achieve the refrigeration system's optimized design parameters, which improve the refrigerator's overall functionality and reduce compressor work.Theoretical calculations can be used to create an optimized design, but they are subject to error because of the ambiguity and complexity when heat transmission from the refrigerant through the condenser tube towards the environment is formulated.To overcome this drawback, the problem is dealt practically.The project entails a trial run of an experimental vapour compression refrigeration system using various capillary tube sizes such as 0.031 in, 0.036 in and 0.042 in and refrigerator charges 100 g, 200 g and 300 g.Modification of Condenser & Evaporator coil subjected to forced convection is also incorporated.Investigation will be carried out for optimum geometry of capillary tube subjected to forced convection by regulating the condenser fan speed from 2 m/s to 3 m/s.Finally, the performance of the refrigeration system will be evaluated on different air velocities.And thus, it was found out that the unit working on the capillary tube of size 0.031in and refrigerant R134a had the maximum COP of 2.85, with refrigerant charge of 300 g at condenser fan speed of 3 m/s.