Experimental Study of the Effect of Nebulizer on the Performance Coefficient of Direct Expansion Air Conditioning Systems

In this experimental study, the condensed water in the evaporator coil was injected using the nebulizer technology into the condenser inlet air and its effect on the performance coefficient was studied. The testing equipment employed in the present study consisted of an air conditioner tunnel with the dimensions of 200×35×35cm, which had the compression refrigeration cycle of 1-ton refrigeration with R404a refrigerant. A data logger with pressure and temperature sensors installed at various points of the unit accurately recorded the measured data. The results indicated that the use of a nebulizer would reduce the compressor outlet pressure and compressor power consumption and also increase the performance coefficient. By increasing the air temperature to the condenser from 21 to 36°C, the use of a nebulizer reduced compressor outlet pressure by more than 27%, decreased compressor power consumption by more than 8%, and increased the performance coefficient more than 64%. The results demonstrate the nebulizer technology could be used on hot days of the year by recycling wastewater from air conditioning systems, as a practical and low-cost method to increase the efficiency of direct expansion air conditioning systems.