Development and validation of a desiccant wheel model calibrated under transient operating conditions

The current study presents model based predictions of a desiccant wheel performance using the transient measurements obtained from a real system. The model is based on a set of equations to simulate the optimal and measured transient performance as a function of measurable input variables related to the desiccant wheel material and structure. The model is adapted to analyze the influence of different working conditions on the desiccant wheel performance: rotation speeds, air velocity, inlet temperature, and inlet air humidity for both process and regeneration air. The model is capable of estimating the optimal rotation speed and pressure drop of the desiccant wheel. Moreover, the developed model can be applied in both, dehumidification and enthalpy modes. The model is validated in comparison to the published data and measurements from the real building desiccant wheel installation. The specific enthalpy at the outlet of process air is considered performance parameter. The obtained results are in agreement with the published data, while the resulting maximum and minimum validation root mean square error (mean percentage error) between the simulated and measured transient performance is 3.6 kJ/kg (4.6%) and 1.9 kJ/kg (0.2%), respectively.