Falling film dehumidification performance on plates with various enhancing elements

Enhanced heat and mass transfer in a falling film liquid desiccant dehumidifier is crucial for improving the efficiency of liquid desiccant air conditioning systems. However, no study has yet been undertaken to examine the impact of a range of different enhancing elements on dehumidification performance. This study comprehensively investigates and compares falling film hydrodynamics and dehumidification performance on plates with various enhancing elements based on different air inlet velocity and humidity, solution inlet velocity, and concentration, as well as enhancing element spacing and height. The results demonstrate that, under a variety of working conditions, the dehumidification performance of the plate with isosceles right triangle shaped finned elements (plate No. 3) is superior to that of other plates. The dehumidification performance of plates with finned elements is superior to that of plates with grooved elements under the same condition. For plates with isosceles right triangle shaped finned elements, the impact of the flow field caused by the elements is greater than in other shapes due to the greater intensity of the gas-liquid perturbation and mixing, resulting in an enhanced dehumidification performance. The findings of this study may prove valuable in the optimization of dehumidifier structures in the context of liquid desiccant dehumidification performance enhancement.