International Journal of Applied Engineering Research

This paper presents an experimental study on the performance of environmentally friendly refrigerants such as R134_a, LPG and LPG/R134_a mixture with and without the effect of magnetic field as suitable replacements for the refrigerant R12 in a vapour compression refrigeration system. Experimental results with no magnets showed that the LPG/R134_a mixture had 6.5% higher refrigerating capacity than that of R134_a and 4.2% lower than R12 for higher evaporating temperatures. The LPG/R134_a mixture had lower refrigerating capacity than that of R12 and R134_a at lower evaporating temperatures. The coefficient performance of LPG/R134_a mixture increased from 2.6% to 5.9% than R12 at higher evaporating temperatures while decreased from 6.4% to 30.4% at lower evaporating temperatures. The compressor power consumption of LPG/R134_a mixture was reduced from 2.5% to 10.3% than that of R12 for all the range of operating conditions. The refrigerating effect, COP and power consumption of LPG was lower than that of R12, R134_a and LPG/R134_a mixture.

Experimental results with the effect of magnetic field force showed that the compressor consumed 1.6 – 2.1% less energy than with no magnets. The behaviour of refrigerants varies from one refrigerant to another depending upon the mixture's composition and its boiling point. The effect of magnetic field force increased coefficient of performance of the system in the range 0.15 – 1.7%. There was no significant influence in the thermal capacities of the condenser and evaporator, discharge pressure and temperature of these selected refrigerants under magnetic field. The LPG/R134 (60/40 by wt.%) mixture can be considered as an excellent alternative refrigerant in CFC12 system. LPG can be considered as an alternative refrigerant for higher evaporating temperatures in a CFC12 system.