Abstract
The effectiveness of using wetted cellulose pads on improving the performance of two conventional passive cooling systems has been evaluated. First, an experimental design was developed to determine the impact of using a wetted cellulose pad on the temperature and velocity of the airflow. A cellulose pad (7090 model) with a cross-sectional area of 0.5 × 0.5 m2 and three different thicknesses of 10, 15, and 30 cm were selected and tested. The results indicated that using wetted cellulose pads with thicknesses ranging from 10–30 cm decreased the outlet airflow temperature from 11.3 to 13.7 °C on average. For free airflow at velocity 3.5 m/s, the outlet airflow velocity from the wetted cellulose pad decreased to 0.9, 0.7 and 0.6 m/s, respectively, for cellulose pads with thicknesses of 10, 15, and 30 cm. By applying experimental results on a psychrometric chart, the humidity ratio of outlet airflow was obtained between 40–70%. The study established airflow velocity as the critical parameter in passive cooling systems. With the novel concept of combining wetted cellulose pads for passive cooling systems (i.e., wind catchers and induced ventilation), there is good potential to reduce the energy requirements for thermal comfort in buildings in regions with a hot and arid climate.
Highlights
The rising demand for cooling and thermal comfort, with consequential increases in energy consumption in the building sector, is an emerging concern
Due to the importance of the airflow velocity and temperature on creating thermal comfort conditions in buildings, numerous tests were performed in this study to establish how much the airflow velocity and temperature decreased after passing throughout a wetted cellulose pad
Outlet airflow velocity and temperature were measured for three cellulose pad thicknesses with five different inlet airflow temperatures
Summary
The rising demand for cooling and thermal comfort, with consequential increases in energy consumption in the building sector, is an emerging concern. Data on energy consumption show that about 40% of total energy consumption, and up to 30% of the world’s CO2 production, is related to the building sector. In the United States, 20% of the total energy consumption, and 50% of energy consumption in buildings is related to air conditioning systems [1,2,3]. Among different passive ventilation methods, the utilization of wind as a passive energy source to create comfortable conditions in buildings has been a common method from ancient times. In central and southern parts of Iran, wind catchers, i.e., Badgirs, have been used as an effective method for cooling homes.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
