Effect of air inlet velocity on air water harvester with small tube evaporator

During the dry season, parts of Indonesia experience drought and clean water crises.  One of the efforts to obtain clean water was by presenting a machine called air-water harvester.  The amount of water mass produced depended on several variables such as RH, intake air temperature, type of condensing unit, intake air velocity and engine power.  This study aims to determine the performance of the air-water harvester at various inlet air velocities.  The dependent variables expected were the mass of water produced, COP, and the amount of heat absorbed from the air.  This research was carried out experimentally with the working fluid refrigerant R134a.  The compressor used was a rotary type 1 PK compressor.  This study varied the air velocity entering the evaporator, namely 1.5 m/s, 3 m/s and 4.5 m/s.  The results showed that the highest mass of water was 0.728 kg.  Meanwhile, the highest COP was 5.13, and the total heat transfer rate absorbed by the evaporator was 160.38 W. All were obtained at the air velocity of 4.5 m/s.