Performance Of A Personalized Ventilation Air Terminal Device At Two Different Turbulence Intensities

The performance of an air terminal device (ATD) supplying personalized air of two levels (20% and 45%) of initial turbulence intensities (Tu) was examined independently using a breathing thermal manikin and twenty four tropically acclimatized subjects. The experiments were conducted in an indoor environment chamber, where ambient air temperature was controlled at 23.5 degrees C and 26 degrees C by a conventional total-volume ventilation system. An independent personalized ventilation (PV) system delivered conditioned outdoor air through the ATD at 9 levels of personalized air flow rates (ranging from 3 to 18.8L/s), and 3 levels of personalized air temperature (21, 23.5. and 26 degrees C), at each of the ambient temperature setting. Manikin measurements revealed that Tu levels do not influence the cooling effect on the body as a whole, although PV air supply at higher Tu was found to be able to prevent the concentration of cooling of the facial area through enhanced mixing. Subjective votes (thermal sensation) were consistent with these measurements and supported the finding that concentration of PV supply air at lower Tu would not be preferred over a more dissipated one with higher Tu for the same supply flow rate and temperature.