ABSTRACT
Ventilation systems have been widely used to satisfy the occupants' indoor air quality and thermally comfort conditions. Various air distribution systems have been developed to supply clean air, including mixing, displacement, and diffuse ceiling ventilation systems. Diffuse ceiling systems are recent air distribution systems that supply cold air to the occupant area using perforated diffuse panels. These systems distribute air with a low velocity, minimizing the draft risk and dissatisfaction in highly dense spaces. The transmission risk of airborne infectious diseases like Covid-19 from the infected patient is high in waiting rooms. Thus, there is a demand to assure a secure environment for medical staff and patients in the waiting rooms. This study aims to numerically investigate the impact of the relative distance of the contamination source and exhaust on the transmission of airborne infectious diseases in the waiting room equipped with the diffuse ceiling ventilation system. In this regard, the release of Covid-19 from 4 different patients was investigated separately using the computational fluid dynamics technique. The distribution of the airborne infectious diseases is simulated by releasing SF6 tracer gas. The simulation result revealed that the contaminated patient located adjacent to the room's outlet had no contamination risk for other patients and staff in the waiting room. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.
ABSTRACT
This study is the first step towards a broader research intent: developing and optimising a Personal Comfort System for tertiary sector working environments. The entire industrial sector, and in particular offices, have seen changes in working habits, with a large increase in smart working to prevent COVID infection. The chance to partialise the HVAC system and maintains the rooms in an under-conditioned state is the obligatory way towards reducing energy waste, providing each workstation with an independent system that guarantees the operator's comfort conditions. The first step of the analysis was conducted simulating a general scenario and adopting conservative assumptions in order to predict the potential energy savings and the required PCS power. BES and CFD were coupled, using the outputs of the dynamic energy simulations in its most energy demanding timestep as input for the fluid dynamics analysis. The results showed energy savings between 15 and 20%, which is likely an underestimation of the potential savings due to very conservative assumptions and looking at the data from the few field analyses available in literature. Moreover, the operators' localised thermal comfort conditions improved, moving from a slightly cold to a neutral situation. Despite the conservative hypothesis, the results are promising, showing several opportunities for further analysis and improvement, as well as possible ways for its optimisation. © 2021 IEEE