Full Description

Providing acceptable thermal comfort and breathable indoor air quality (IAQ) in university classrooms is crucial to maintain the students' wellbeing and decision-making abilities. These are achieved by maintaining indoor temperature, relative humidity (RH) and CO2 concentrations within acceptable ranges. For this reason, ventilation, and air conditioning (VAC) systems are used to supply large amounts of dry cool ambient air. Conventionally, these VAC systems use vapor compression systems to dehumidify the ambient air by cooling it below its dew-point temperature. The air must then heat to the required supply temperature to avoid causing draught discomfort, leading thus to energy intensive cooling systems. However, this cooling system's size can be reduced by separating the latent and sensible loads. This is achieved using solid desiccant that adsorbs excess water vapor from the ambient air, while the vapor compression handles the sensible cooling load. Moreover, commercial desiccants such as silica gel showed good adsorption capacity with low regeneration energy and temperature that enables the use of low-grade thermal energy. Additionally, the desiccant regeneration airflow carrying the desorbed water provides a potential free source of fresh water. By cooling the regeneration airflow that is typically discharged to the environment, water vapor can be condensed. Therefore, the hybrid desiccant--vapor compression system can provide the cooling needs of a classroom and produce potable water for students' consumption. Validated mathematical models were used to assess the integrated systems ability in maintaining acceptable thermal comfort and IAQ levels while producing water at minimal energy consumption. The simulations were carried out for the peak load month for a case study of an occupied classroom located in the hot and humid climate of Beirut, Lebanese. Compared to the conventional system, the proposed system was able to reduce the thermal and electrical energy consumption by 30 % and 41 %, respectively, with 83 % higher freshwater production during the peak load month August.

Product Details

Published: 2022 Number of Pages: 8 Units of Measure: Dual File Size: 1 file , 1.1 MB Product Code(s): D-ICEB22-06 Note: This product is unavailable in Russia, Belarus