The Effect of Air Velocity Changes on Perceived Temperature, Comparison Of Continuous and Pulsed Airflow
DOI:
https://doi.org/10.66987/EPKO.2026.16Keywords:
thermal comfort, PMV, draught rate (DR), turbulence intensity, pulsating air supply, simulated natural air movement, dynamic air velocityAbstract
The character of indoor air movement — particularly the comparison between steady, laminar air supply and time-varying, pulsating jet techniques — has emerged as a key question in HVAC comfort research. Based on a systematic review of the relevant international literature, this paper investigates how the fluctuation characteristics, turbulence intensity, and pulsation frequency of air velocity influence occupants' thermal sensation, the draught rate (DR) characterising draught discomfort, and overall thermal comfort as defined by the PMV–PPD indices. The analysis demonstrates that pulsating air supply modes and those simulating natural air movements deliver more favourable comfort outcomes than steady air velocity under a wide range of conditions, while also offering opportunities to reduce energy consumption.
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