Assessment age of air and thermal comfort in a classroom by adopting displacement ventilation with chilled ceiling system

This study aims to investigate the effect of the cooling load ratio covered by the chilled ceiling on the age of air and comfort level in a classroom in a hot and dry climate in Iraq-Hilla city. Air age, air exchange efficiency, and concentrations of pollutants in a classroom are investigated numerically by used AIRPAK software under displacement ventilation combined with a chilled ceiling system. Four cases are studied at different values of the cooling load covered by the chilled ceiling (0%, 25%, 50%, 80%) with respect to total classroom cooling load. Cooling load removes by chilled ceiling varied from (0 to 84.5 W/m2) based on the classroom area, and its temperature varied between (17.5-22.5oC). The displacement ventilation airflow rate was kept at 0.3m3/s, and the air temperature supply varied between (19.5-24.5oC) depend on the amount of cooling load covered by displacement ventilation. The results showed that the mean local air age increasing with height. The room mean air age increase and air exchange efficiency reduce with increasing load portion, which treated by the chilled ceiling. Increasing the portion of the load treated by chilled ceiling tends to improve comfort levels.

A Glance on Radiant Cooling Technology for Heating and Cooling for Residential and Commercial Building Application

As we know that nowadays due to the hot and humid weather and the increasing temperature the high amount of energy consumption is used for the heating & cooling purpose in residential as well as in commercial building for air conditioning systems. To overcome this problem and to reduce the energy consumption as well as good thermal comfort to people in the indoor environment, use the radiant heating & cooling system is a better way. This concept is used to cool or heat the room and absorbs the indoor sensible heat by thermal radiation. The system removes heat by using less energy and more energy-efficient. This system uses water as a medium to cool or heat the room space. There are three types discussed in these papers for cooling & heating. In this paper, we did an overall study regarding radiant heating and cooling systems. It reduces the energy lost due to the duct leakage. It also has a lower life cycle cost compared to conventional. In this paper, we have reviewed how to reduce energy consumption and give thermal comfortable air-condition through radiant cooling and chilled ceiling panel system.