Performance studies on a water chiller equipped with natural fiber cooling pad based evaporative condenser

Abstract

The finned heat exchanger is commonly used as air cooled condenser in small-capacity water chillers and air conditioners. Its heat duty diminishes during peak Indian summer. During these severe conditions, a heat exchanger incorporated with evaporative cooling techniques improves condenser performance and reduces compressor power consumption. When these heat exchangers are combined with cooling pads, which are effectively used in direct evaporative cooling techniques, the heat rejection capacity is improved. Pad material, thickness, and specific contact area are some of the parameters used, in assessing heat exchanger duty. This research work deals with experimental testing of the condenser performance of a water chiller with jute, cotton, and coconut fiber cooling pads. Also, the positioning of the pad concerning the heat exchanger and fan has been varied to assess the heat rejected from the condenser. When the cooling pad is placed in between the fan and condenser, all three pads exhibit enhanced performance in removing heat from the condenser due to better utilization of evaporative cooling. Out of the three pads, jute fiber performs better, where chilling is 23.5 % faster when compared with cotton fiber and 47.1 % faster when compared with coconut fiber. When the jute fiber pad is placed in between the fan and condenser, the water chilling rate is better by 76.5 %, when compared with pad positioning before fan and condenser and 11.8 % when compared with pad positioning after fan and condenser.