• Stratum ventilation;
  • Effective draft temperature;
  • Air diffusion performance index;
  • Thermal sensation;
  • Uniformity


Three human test series were conducted to evaluate the uniformity of the thermal environments in a stratum-ventilated chamber with dimensions of 8.8 m (L) × 5.1 m (W) × 2.4 m (H). In all, nineteen conditions were generated by adjusting the room temperature, supply airflow rate, and supply terminal type. An air diffuser performance index (ADPI) of at least 80% was achieved for most cases. This result shows that the air velocity and temperature in the occupied zone are reasonably uniform. Subjective assessments using the ASHRAE 7-point scale indicate that the thermal sensations of the subjects in stratum ventilation are also uniform. This study examines the applicability of the predicted mean vote (PMV) model for evaluating stratum ventilation. When compared to the actual mean thermal sensation votes (ATS), the PMV values are acceptable. The PMV results at a height of 1.1 m above the floor show better agreement with the ATS than at a height of 0.1 m.