Experimental Analysis of the Performance of Vapor Compression Refrigeration System Using R134a, R290 and R404a with Several Diameters of Capillary Tube

The main objective of this work is to enhance the performance of the domestic refrigerator .To attain this analysis is carried using the combination three different refrigerants (R134a, R290 and R404a) & three different inner diameters (0.3mm, 0.45mm, 0.50mm) of capillary tube. Comparing the performance parameters of the refrigeration system with different refrigerants & different capillary tube by keeping ambient temperature and compressor discharge constant for all the combinations, it is found that the COP of the system is better for the capillary diameter of 0.30mm for all three refrigerants R134a, R290 and R404a. As we increases the diameter of capillary tube the cop tends to decrease. Whereas, refrigeration effect value did not follow any regular trend. Highest cop value for refrigerant R134a is recorded for 0.30mm diameter of capillary tube which is 3.94. For R290 it is recorded as 3.19, for capillary diameter of 0.30mm. The same size of capillary (i.e. 0.30mm) gives optimum value of cop for R404a, which is 1.46.