Influence of porous condenser on the performance of a split air conditioner

Condensation is a main process in the compression refrigeration cycles. The low performance of split air conditioners prompted researchers to find different methods to improve their performance. One of the methods that can be used to enhance the performance of split air conditioners is the use of porous inserts in the tubes of the condenser. An experimental test rig, which consists of a compressor, condenser, expansion valve, and evaporator, is used for this issue. Stainless steel balls with porosities of 49%, 38%, 30%, and 100% were used. The condenser temperature was varied from 30 to 44 °C, while the air ambient temperature varied from 27.5 to 37.5 °C. The tested refrigerant is R454C. Evaporation capacity, coefficient of performance, power consumption, and volumetric evaporation capacity are experimentally investigated for different operating parameters. Heat rejection rate, mass flow rate, pressure drop, and compressor discharge temperature are also investigated. Percentages of increase of 53.3% and 25.7% are recorded for cycle coefficient of performance and power consumption, respectively, by changing porosity from 100 to 30%. Also, average percentages of increase of about 50.5% and 35.5% are recorded for heat rejection rate and pressure drop, respectively. The coefficient of performance and evaporation capacity are increased by 58.4% and 63.9%, respectively, when decreasing air ambient temperature from 37.5 to 27.5 °C. Power consumption increases by 26% when increasing air ambient temperature from 27.5 to 37.5 °C. Compressor discharge temperature considerably increases at high condensing temperatures and low porosities.