Performance of radiant cooling ceiling combined with personalized ventilation in an office room: Identification of thermal conditions

The paper compares thermal environment conditions created by four HVAC systems: mixing ventilation, chilled ceiling combined with mixing ventilation, chilled ceiling with mixing ventilation and personalized ventilation, and chilled ceiling combined with personalized ventilation only. Measurements were performed in a test room arranged as an office with 2 workstations and 2 seating occupants resembled by thermal manikins. Heat gain of 66-72 W/m² was simulated in the room (occupants, computers, lighting, solar gain). The air temperature in the chamber was maintained at 26°C and 28°C. Personalized ventilation supplied air at non-isothermal condition with temperature of 25°C. Results showed that the compared methods generated almost the same thermal environment in the occupied zone. However at the workstations the personalized ventilation combined with chilled ceiling provided more cooling and decreased the radiant temperature asymmetry created by the simulated warm window surface. Chilled ceiling combined with PV alone may be applied successfully in practice.