Effect of Outdoor Heat Exchanger Designs on the Performance of Residential Heat Pump System

Finned tube heat exchangers are widely used as evaporators and condensers in residential air-conditioning and heat pump systems. Thermo-hydraulic performance of finned tube heat exchangers in residential heat pump systems is influenced by their geometrical parameters and refrigerant circuits. In order to improve the performance of these heat exchangers, a detailed numerical investigation on outdoor unit was carried out in this study. Cycle simulations for heat pump system were performed for standard cooling and heating conditions using cycle simulation software. The results were validated with the experimental data. The maximum percentage differences were 0.38% in EER and 1.64% in COP. Further, the effect of different geometric parameters like tube’s length, no. of tube rows, fin pitch, circuit design and tube inlet position on system performance were studied. Length of the tube was varied from 800mm-2800mm, no. of tube rows were varied from 2-10 and fin pitch was varied from 1.3mm to 1.9mm. Moreover, 10 different circuit designs, three cases for inlet positions were also analyzed each for 17, 18 and 19 number of inlets. From the selected ranges of these parameters, it has been concluded that all these parameters have significant effect on system performance.