Dehumidifier Parametric Analysis

The dehumidifier parametric analysis will investigate the effect: inlet air relative humidity, inlet air temperature, inlet air velocity, desiccant solution mass flow rate and desiccant solution mass concentration have on the overall performance of the dehumidifier. These variables have been selected due to their influence on overall dehumidifier performance. The dehumidifier parametric analysis is based upon the information listed in Tables 3.9 and 3.10. The volumetric air flow rate has been selected based on achieving a change in absolute humidity across the dehumidifier of 0.01 kg/kg; an acceptable value for air conditioning applications. The convective heat and mass transfer coefficients listed are for the stated boundary conditions.

Figure 3.14 demonstrates the dehumidification process on a psychrometric chart. Based on the dehumidifier base simulation conditions, the process air is conditioned to a temperature of 26 °C and 61 % RH. The reduction in absolute humidity of the process air across the dehumidifier is 0.01006 kg_vapour/kg_dryai_r, an acceptable value for air conditioning applications (Jradi and Riffat 2014a). At the dehumidifier outlet the desiccant solution temperature is 25.3 °C, with a solution mass concentration of 0.6948. The overall dehumidification and cooling capacity is 1772 W, at a latent and enthalpy effectiveness of 44.93 and 47.1 % respectively.

Fig. 3.14 The dehumidification process shown on a psychrometric chart