Development of an experimental validated model of cross-flow indirect evaporative cooler with condensation

Abstract The indirect evaporative cooling (IEC) is regarded as a low-carbon and energy efficient technology to reduce the cooling load of an air conditioning system. However, in hot and humid areas, condensation might take place in fresh air channels of IEC unit. Although the heat and mass transfer model of one-dimensional counter flow IEC has been established with consideration of condensation from fresh air. However, the two-dimensional cross flow IEC model considering condensation has seldom been investigated and experimentally validated. Therefore, this paper presents a two-dimensional analytical model of cross-flow IEC considering condensation from fresh air. FEM (Finite Element Method) is used to solve the model. Besides, a test rig with visualized air channel has been designed to verify the accuracy of the developed model. The performance of IEC unit and its visualized condensation behavior under various conditions were intensively studied. The results show that the condensation is more likely to take place near the outlet of fresh air and inlet of exhaust air in cross-flow IEC unit. The latent heat transfer could reach up to 3.9 kW and around 30% moisture content of fresh air would be removed under full condensation states. The water consumption in IEC unit depends on the total heat transfer rate and ranges from 1.2 L/h to 6.6 L/h under various operating conditions.