Experimental Study of Chair Ventilation in Office Cubicles

Nowadays over 80% of our daily time are spent indoors. A good indoor environment is quite important to our health and performance. To achieve this goal, different kinds of ventilation systems have been developed and used in practice. Conventional ventilation systems such as mixing system and displacement system are facing challenges such as meeting personal preference, enabling local and fast dynamic control, and avoiding cross infection and high energy consumption.

Personalized ventilation (PV), supplying clean and comfortable air directly to the occupants and improving the thermal comfort and air quality around the subject, has the potential to be a better and more efficient approach for individual space conditioning and air delivery. However the high draft due to the jet and inability to fulfil the thermal comfort requirement all around the occupant also makes its application a challenge. In this study, a newly developed chair ventilation (CV) device mounted in an office cubicle was evaluated in terms of thermal comfort and air quality using a thermal manikin. Both temperature and velocity distribution are measured in the occupied space. Thermal comfort analysis using equivalent temperature is applied on totally 19 parts of the manikin. Tracer gas measurements have been performed to determine the contaminant removal efficiency of the CV in two cases in which the contaminant source is located either inside or outside the cubicle. Both the thermal environment result and air quality result were compared with that obtained from the experiment of under-floor air diffuser (UFAD) system and desk-mounted personalized ventilation system (PV). It can be concluded that chair ventilation system can generate a more uniform temperature field all around human body with the lowest draft even though there is some unexpected local cooling. Tracer gas test shows the performance of each system depends on the location of the contaminant source and correlation with the cubicle configuration.