Performance of an innovative personalized ventilation mode based on air attachment under non-isothermal air supply conditions

In view of the shortcomings of traditional personalized ventilation method, an innovative mode of personalized ventilation was explored in this study. To investigate the performance of the personalized ventilation mode, velocity field measurements were performed to examine the impact of the supply air temperature on the airflow distributions, and a tracer gas system was used to test the fresh-air ratio in the breathing zone. The results show that the critical supply air velocity increases as a function of the supply air temperature and that the position height of the air attachment formation is a decreasing function of the supply air temperature. The fresh-air ratio in the breathing zone was significantly correlated with the formation and height of the attachment. Furthermore, the higher the position of the air attachment formation, the greater the breathable fresh-air ratio. The breathable fresh-air ratios were 83.3 %, 82.3 % and 84.1 % at supply air velocities of 0.3 m/s, 0.4 m/s and 0.5 m/s, respectively, and a supply air temperature of 17 degrees C. Compared with the traditional air supply method, the ventilation effectiveness of the the air dress personalized ventilation(ADPV) method in this study is highest. Irritation in the eyes was weaker than that in other areas. Irritation in the lips and nose was an increasing function of the supply air velocity, and no obvious connection with the supply air temperature. Furthermore, the supply air velocity and temperature significantly influenced the sensation in the upper body; however, no obvious influence was observed on the sensation in the lower body. It was verified that the ADPV method was able to satisfy the requirements of human comfort and the breathable air quality simultaneously.