Heat Transfer Analysis of Environment-Friendly Refrigerants Using Conventional and Minichannel Condensers in Versatile Refrigeration Systems

The refrigeration system is fabricated so that it can control multiple input and output parameters for testing different refrigerants in the same system at the same condenser and suction pressure and temperature.The suction temperature in the evaporator was varied with controlled water heaters, the condenser temperature was controlled by air heaters and a multispeed fan, and different temperatures at salient points were precisely varied by the PID controller, expansion valve was used to use different refrigerants.The conventional copper tube condenser and aluminum mini channel parallel flow condenser were used to test R134a, R152a, R600a, R290, and a mixture of R290/R600a (50/50% by mass) refrigerants for varying condensation temperatures in the range of 30 to 55 and evaporation temperatures in the range of -10 to 15.The refrigerant charge was drastically minimized by 35% for R152a, 60% for R600a, R290, and a mixture of R290/R600a (50/50% by mass) with the minichannel condenser over conventional round tube plate fin condenser due to compact minichannel condenser.It was observed that volumetric refrigerating capacity was higher by 8%, power input to the compressor was reduced by 9%, coefficient of performance was increased by 14%, refrigeration capacity was decreased by 9%, and condenser capacity was reduced by 15% for minichannel condenser over conventional condenser at a condensing temperature of 44 and evaporative temperature of 0.