Application-specific performance assessment of desiccant wheel design and operational parameters for industrial drying and HVAC dehumidification

Moisture removal with desiccant wheels is widely recognized for being effective and energy-efficient across various applications. Their effective dehumidification and energy efficiency performance is influenced by a combination of design and operational parameters. However, most existing studies investigated different parameter sets and employed diverse performance indicators and definitions, making it difficult to determine whether parameter assessments obtained for one application remain applicable to another. This study investigates how application-specific expectations for performance indicators affect the assessment of desiccant wheel design and operational parameters. Industrial drying and heating, ventilation and air-conditioning (HVAC) dehumidification applications are considered as two illustrative applications with different requirements for process outlet air conditions, and the analysis is conducted under hot/humid and cool/humid process inlet air conditions, corresponding to 30 °C/85% relative humidity (RH) and 20 °C/85% RH, respectively. The results show that regeneration inlet air temperature produced the largest overall performance variations, followed by wheel rotation speed and regeneration air velocity, although their effects differed among dehumidification performance, dehumidification coefficient of performance (DCOP), and sensible energy ratio (SER). Regarding design parameters, in drying application, the process/regeneration area ratio ( φ ) exhibited the highest normalized Morris sensitivity for most of the evaluated indicators. Under the HVAC–hot/humid baseline, coating amount exhibited the highest normalized Morris sensitivity for most indicators, whereas the process-to-regeneration area ratio was more influential for most dehumidification-related indicators under the HVAC–cool/humid baseline. The results show that performance objectives determine the desired directions and relative priorities of the KPIs, which may lead to different preferred parameter settings within the investigated conditions and parameter ranges. The results offer valuable insights into the design and operation of desiccant wheels, aiming to enhance their application in fields such as HVAC systems and industrial drying processes.