Performance of Ductless Personalized Ventilation in Conjunction with Displacement Ventilation: Impact of Workstations Layout and Partitions

The performance of a new personalized ventilation system, referred to as ductless personalized ventilation (DPV), was studied in full-scale room experiments in conjunction with displacement ventilation (DV). The idea behind DPV is to utilize clean and cool air supplied via DV. In the experiment, the DPV, consisting of an air supply terminal device, a small fan, and a short duct, sucked clean air from floor level near the desk.

The performance of the DPV system was evaluated under various arrangements of two identical workstations. Two breathing thermal manikins were used to simulate seated occupants. Two tracer gases, one mixed with the air exhaled by one of the manikins and the other generated on the table in front of the same manikin, were used to simulate pollution.

When the DPV system was operational, the inhaled air was as clean as the air inhaled using only the D V alone and even cleaner for some of the layouts studied. The use of DPV in conjunction with DV substantially decreased the temperature of the inhaled air and increased the body cooling in comparison with use of DV alone, i.e., DPV also had potential for improving occupants' perceived air quality and thermal comfort.