After the concept of personalized ventilation came up, a lot of studies about thermal comfort have been done and found out many parameters that influence people’s thermal comfort. In the present research, the influence of the following parameters on air movement perception, thermal sensation and thermal comfort were studied: a new parameter: the airflow distance between the subject and the air duct, the joint effect of airflow speed and airflow fluctuating period. 25 samples of subjective thermal comfort experiment were carried out and analyzed; a CFD simulation was done and used as an explanation of the result from field experiment.

Under the same mean airflow speed, a longer distance results in a cooler thermal sensation due to the increase of exposure area and turbulence int...[ Read more ]

After the concept of personalized ventilation came up, a lot of studies about thermal comfort have been done and found out many parameters that influence people’s thermal comfort. In the present research, the influence of the following parameters on air movement perception, thermal sensation and thermal comfort were studied: a new parameter: the airflow distance between the subject and the air duct, the joint effect of airflow speed and airflow fluctuating period. 25 samples of subjective thermal comfort experiment were carried out and analyzed; a CFD simulation was done and used as an explanation of the result from field experiment.

Under the same mean airflow speed, a longer distance results in a cooler thermal sensation due to the increase of exposure area and turbulence intensity, but it do not cause any difference in thermal comfort. The fluctuating amplitude and period have impact on the β value of its spectral characteristics. Fluctuating period influenced air movement perception: a shorter fluctuating period results in a higher air movement perception. Sinusoidal wave airflow changing the fluctuating period from 10s to 60s were shown to have no influence on thermal sensation vote under sedentary condition in this study and this finding was similar with that recorded in previous studies. However, this study shows that the airflow speed and the fluctuating period had joint effect on thermal comfort vote. Subjects prefer to have a proper air movement under neutral-warm environment, especially when low airflow speed was provided.