TY - JOUR
T1 - Theoretical analysis of transient heat and mass transfer during regeneration in multilayer fixed-bed binder-free desiccant dehumidifier
T2 - Model validation and parametric study
AU - Shamim, Jubair A.
AU - Paul, Soumyadeep
AU - Hsu, Wei Lun
AU - Kitaoka, Kenji
AU - Daiguji, Hirofumi
N1 - Publisher Copyright:
© 2019 Elsevier Ltd
PY - 2019/5
Y1 - 2019/5
N2 - A numerical model is presented for the prediction of transient heat and mass transfer characteristics during the regeneration process in a multilayer fixed-bed, binder-free desiccant dehumidifier. Experiments were carried out in a previous study that provided the benchmark data for validation of the current model under different temperatures and velocities of the regeneration air. A spherical microsphere silica gel having a pore diameter of 2.7 nm was used as the adsorbent during the experiments. In the first part of this study, model validation was performed for different temperatures (314.4–325.0 K) and velocities (0.6–0.9 m s−1) of regeneration air. The results showed that at a fixed regeneration temperature (325.0 K), the model predicted mass of the desorbed water as well as the desiccant bed and air temperatures were in a good agreement with the previously reported experimental results. With a decrease in the temperature and velocity of the regeneration air, the model slightly underpredicted the experimentally obtained mass of the desorbed water; however, the deviation remained within a reasonable limit. Upon validation, a parametric study was carried out to show how the heat and mass transfer characteristics of the microsphere silica gel during desorption depended on the intrinsic material properties (e.g., desorption rate constant, diffusivity, and desorption isotherm) and mechanical design parameters of the device (e.g., convective heat transfer coefficient, porosity, and thickness of the desiccant bed).
AB - A numerical model is presented for the prediction of transient heat and mass transfer characteristics during the regeneration process in a multilayer fixed-bed, binder-free desiccant dehumidifier. Experiments were carried out in a previous study that provided the benchmark data for validation of the current model under different temperatures and velocities of the regeneration air. A spherical microsphere silica gel having a pore diameter of 2.7 nm was used as the adsorbent during the experiments. In the first part of this study, model validation was performed for different temperatures (314.4–325.0 K) and velocities (0.6–0.9 m s−1) of regeneration air. The results showed that at a fixed regeneration temperature (325.0 K), the model predicted mass of the desorbed water as well as the desiccant bed and air temperatures were in a good agreement with the previously reported experimental results. With a decrease in the temperature and velocity of the regeneration air, the model slightly underpredicted the experimentally obtained mass of the desorbed water; however, the deviation remained within a reasonable limit. Upon validation, a parametric study was carried out to show how the heat and mass transfer characteristics of the microsphere silica gel during desorption depended on the intrinsic material properties (e.g., desorption rate constant, diffusivity, and desorption isotherm) and mechanical design parameters of the device (e.g., convective heat transfer coefficient, porosity, and thickness of the desiccant bed).
KW - Material properties
KW - Mechanical design parameters
KW - Multilayer sheet-type desiccant dehumidifier
KW - Numerical simulation
KW - Regeneration process
UR - http://www.scopus.com/inward/record.url?scp=85060681012&partnerID=8YFLogxK
U2 - 10.1016/j.ijheatmasstransfer.2019.01.094
DO - 10.1016/j.ijheatmasstransfer.2019.01.094
M3 - Article
AN - SCOPUS:85060681012
SN - 0017-9310
VL - 134
SP - 1024
EP - 1040
JO - International Journal of Heat and Mass Transfer
JF - International Journal of Heat and Mass Transfer
ER -