Performance comparison and exergy analysis of different flow types in internally-cooled liquid desiccant dehumidifiers (ICDs)

Abstract

In the present study, performance comparison and exergy analysis of different flow types in internally-cooled liquid desiccant dehumidifiers (ICDs) were conducted. Moisture removal rate, exergy efficiency and unmatched coefficient are adopted, to analyze performance of ICDs under different flow types. Sensitivity analysis of each operating parameters as well as their influence on the performance difference among different flow types were carried out. Finally, the design suggestion on choosing flow types for ICD was given. It was found that counter flow arrangement between air and cooling media has shown higher moisture removal rate and lower exergy destruction among all flow types. It was proved that more evenly distributed heat and mass transfer driving force can help decrease the device exergy destruction as well as improving the overall device performance. Thus, the performance of ICD can be improved by decreasing the desiccant solution mass flow rate, lowering the desiccant solution inlet temperature. As for further dehumidifier design, flow type with counter flow between air and cooling media and cross flow between air and desiccant solution is recommended.