Investigation on the chlorine free
HFC refrigerants which have both
advantages of HFC and HCFC. So the new study on blending of hydroflurocarbon
takes place and new gases are formed such as R507A and R417a. All the Blend mixtures are not the solution for the
replacement of existing refrigerant
because GWP of the mixed refrigerant should be less than present using
refrigerant. Among the blend mixtures, R417a had given the better results and
had capacity to replace the present using R22 applications. R147a utilises less
power consumption than R22 where the experiment carried on the same apparatus
and same operating conditions. Refrigerant R417a comprises of R125, R134 and
R600.
Binit
Kumar Jha has done the theoretical study between the eco friendly R600a
refrigerant and the widely used R134a refrigerant and observed that the
discharge pressure of R600 is less than
that of R134a and the refrigerant effect and the coefficient of performance is
comparatively high for R600a than R134a.
Adil
F. Momin and Manish H. Attal carried out
experimental tests on the domestic refrigerator
using phase change materials with R290/R600a blend as a refrigerant,
while the PCM used is ethylene glycol, coated on the back side of the
evaporator. Addition of PCM enhance the heat transfer and increases the
evaporator temperature. Thermal energy stored in the PCM is used during the off
cycles which helps in the continuous refrigeration operation.. This lead to
increase in the coefficient of performance and decrease in the refrigerant
cycling time.
Research
to find a replacement refrigerant R134a have been carried out by several
previous researchers. Prayudi and Roswati Nurhasanah also had a performance
analysis on the R600a and R134a refrigerants with the subcooling effect using
the liquid suction heat exchangers with cooling load. Cooling load variations
are done by opening the valve at different positions. There is no impact on the
compressor work due to cooling load and compressor work increases with the
subcooling effect. Greater the sub cooling temperature, greater the temperature
drop in the evaporator and R600a is giving better results when compared to
R134a.
Prayudi Suparmin has done a
experimental analysis on the different refrigerants for different degree of
subcooling. He had used the liquid suction heat exchanger for the different
degree of subcooling and said that on subcooling the refrigerant which tends to
prevent the flash gas formation at the throttle valve. From the experiment he
showed, the effectiveness of LSHE increases with the increase in degree of
subcooling. He showed the mixture of R290 and R600a in the ratio of 50:50 in a
refrigeration system is having the highest effectiveness of LSHE when compared
to other refrigerants.
