Subjective assessment of thermal comfort in rooms served by the novel enhanced displacement ventilation system with different airflow discharge angles

Abstract

The performance of conventional displacement ventilation (DV) system in a mock-up office was enhanced by a novel way of transporting cooler air from the floor level to the occupant's torso with the aid of 4 fans mounted at each corner of a chair. The subjective assessment of indoor thermal comfort served by the novel enhanced DV system was carried out with the room air temperature at 1.1m height maintained at 26±0.5°C. Thirty-two tropically acclimatized college-aged subjects participated in this study. Each subject had individual control of the air velocity at 3 air speeds and the position of the fans at 0°, 30°, and 60° to the horizontal plane. The result of this study has re-confirmed that the fans at warmer room temperature significantly improved the thermal comfort of occupants. The result also showed that the fan position angle of 30° to the horizontal plane was most preferred by the subjects.