Controlling Temperature and Relative Humidity of Ventilation Air by using a Cooling Coil and Rotary Heat Exchangers.

Dedicated outdoor air systems (DOAS) are used to supply treated outdoor air to a cooled space. This paper focuses on a DOAS and its application in tropical climate. This DOAS is equipped with a desiccant coated Enthalpy Wheel (EW), a dehumidifying cooling coil (CC), and a sensible heat wheel (SW). A mathematical model was developed using the governing equations and validated with a TRNSYS simulation and experimental data with a coefficient of determination of 0.88 and 0.92, respectively. Simulations using the validated model showed that the DOAS configuration was applicable for the tested tropical climatic conditions. Further investigations showed that a maximum change in temperature with respect to rotational speed of SW achieved was 2.44°C, and maximum change in humidity ratio with respect to rotational speed of EW achieved was 0.38%. Also, CC showed a maximum change in temperature of 14.69°C and humidity ratio of 8.35% with respect to chilled water flow rate. Likewise, Air flow rate also showed change in temperature and humidity ratio of the supplied air. [ABSTRACT FROM AUTHOR]