Experimental Study on Performance of Inverter Split Air Conditioner Using r-32 with Evaporative Cooled Condenser

Abstract

To driving durable economic growth and development of any country, the main role is energy. To decrease energy consumption, it is necessary to use an energy inefficient way. Air conditioning systems are used to improve the quality of life and comfort level. Nowadays according to a literature review, 20% world total electricity used in mechanical vapor compression systems. Therefore, if a small amount of improvement of the performance of the vapor compression system, a huge amount of energy will save. Split air conditioning system working on a vapor compression refrigeration cycle in which air cooled condenser is present in the outdoor unit. Air-cooled condenser temperature is directly depended on the ambient. Therefore, in a very hot environmental region, the air-cooled condenser temperature and pressure are considerable increases. Consequently increased the power required to run the system because raised the pressure ratio. Increase temperature of condenser also decreases the VCR system cooling capacity due to a decrease in liquid refrigerant entering into the evaporator. Due to these two effect, the performance of the air conditioning system is decreased in very hot ambient conditions. To overcome this situation and improve the performance, decrease air inlet temperature to the condenser by providing evaporative cooling pad before condenser. The main objective of present work is to construct a psychrometry lab for testing of split ac at different artificial ambient conditions and to investigate saving in energy consumption with the use of evaporative cooled condenser. Experiments are performed on 1 TR Split Air Conditioner(Daikin Make 5 stars inverter split air conditioner with R-32 as a refrigerant) with and without cooling pad at a temperature ranging from 35oC to 43oC at the inlet to ODU. Cellulose cooling pad of 100 mm thickness is airtightly coupled to the ODU. The performance of a split air conditioner is experimentally measured by measuring temperature and relative humidity of air inlet and outlet and air flow rate. Overall for any inlet air conditions ranging from 35 C to 43 C, energy saving of about 3.24% to 41.79% is obtained with the evaporative cooled condenser.

Experimental results show that for the 35oC ambient temperature condition, the cooling capacity is increased by 0.47% and power consumption reduced by 41.79% and overall COP increased by 72.60% with the evaporative cooled condenser. Also, for the 43oC ambient condition, it is found that overall COP increased by 23.66%, cooling capacity increased by 19.66% and power consumption reduced by 3.24% with the evaporative cooled condenser. Based on experimental results economic analysis for 1 TR AC running under Ahmedabad’s weather conditions is carried out. It is estimated that energy saving of about 2 Units/day can be achieved using evaporative cooled condenser and accordingly the payback period will be of 3.94 years.