Comparative study on energy consumption and indoor thermal environment between convective air-conditioning terminals and radiant ceiling terminals

Comparative experimental studies on energy consumption and indoor thermal environment between convective air-conditioning terminals and radiant ceiling terminals, as well as the systematic scientific explanations for their differences, were rarely reported. In this study, comparative experiments have been carried out for convective air-conditioning and radiant ceiling terminals to identify their performance differences in terms of energy consumption and thermal comfort in hot summer and cold winter Zone. The data of energy consumption, indoor air temperature, vertical temperature gradient, and horizontal temperature asymmetry were measured and analyzed. The results show that under the same operative temperature, the radiant ceiling terminal (RC terminal) can save 26.53% and 34.75% of energy consumption compared with the convective air-conditioning terminal (CAC terminal) in the cooling and heating test periods, respectively. Meanwhile, the air temperature of the RC terminal room is 2.4 °C higher than that of the CAC terminal room for cooling season and 2.2 °C lower for heating season. The vertical temperature gradient distribution of the RC terminal room is 0.6–1.5 °C/m, which is only 27.5% of that of the CAC terminal room. Moreover, the horizontal temperature fluctuation of the RC terminal room is only 1/3 of that of the CAC terminal room. Therefore, as for considering energy consumption and indoor thermal comfort level, the RC terminal outperforms than the CAC terminal.