Effects of wall thickness on the heat and moisture transfers in desiccant wheels for air dehumidification and enthalpy recovery

Desiccant wheels have two major uses: air dehumidification and enthalpy recovery. In this paper, a two-dimensional coupled heat and mass transfer model which takes into account the resistance in the solid in both the axial and the thickness directions is presented to simulate the heat and mass transfers in a desiccant wheel. Through numerical simulations, the optimum rotary speeds for sensible heat recovery, latent heat recovery, and air dehumidification are calculated. Temperature and humidity profiles in the wheel during both the dehumidification and the enthalpy recovery processes are analyzed. The effects of channel wall thickness on the optimum rotary speeds for the two applications are analyzed.