In this study

an electric-heating film was set up in a climate chamber to simulate the heat transfer in an external building envelope. Then

the indoor air distribution characteristics in a room with chilled ceiling and mixed ventilation were studied when the cooling loads were 83 or 111 W/m2. The results show that a uniform vertical temperature profile below 1.7 m as well as a non-uniform temperature profile above 1.7 m existed when the ceiling surface temperatures varied from 15 to 23 ℃ and the supply air temperature was 22 ℃. The CO2 concentration was large in the occupied zone and small near the ceiling or floor. Moreover

the average vertical air temperature difference

turbulence intensity

and contaminant removal effectiveness were 0.1–0.2 ℃

32%–38% and 0.62–0.86

respectively. Therefore

the changes in the ceiling surface temperature slightly affected the vertical air-temperature difference and turbulence intensity

whereas they clearly influenced the contaminant removal effectiveness.