Effectiveness of Chilled ceiling assisted by intermittent personalized ventilation for active contaminants’ confinement and energy savings D. Al Assaad, K. Ghali and N. Ghaddar   2019/07/15

Abstract

The integration of intermittent personalized ventilation in office spaces equipped with chilled ceiling has been proven to enhance comfort and provide satisfactory indoor air quality. However, in the case where the occupant using the personalized ventilator is infected, the turbulence of the intermittent personalized ventilation jet could enhance contaminant spread and compromise the indoor air quality in the space. In this work, an office space equipped with a chilled ceiling and intermittent personalized ventilation was modelled using a validated CFD model. The intermittent jet was supplied towards an infected occupant. The frequency and average flow rate that could minimize particle spread in the space were investigated. It was found that the intermittent personalized ventilator should be operated at a frequency of 0.3 Hz and an average flow rate of 3.5 L/s. These conditions confined the particles to their source of generation while still providing comfort for the infected occupant.

Authors and affiliations

D. Al Assaad1, K. Ghali1 and N. Ghaddar1
1. Department of Mechanical Engineering. American University of Beirut, Lebanon

Key words

Personalized ventilation, chilled ceiling, active contaminants, energy savings

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