An experimental study of the influence of a walking occupant on three air distribution methods

• The influence of a walking occupant was studied under three air distribution methods.
• Short walk does not cause the airflow pattern to change.
• Stratum ventilation almost keeps its airflow pattern during the walking process.
• Stratum ventilation has the potential for application with frequently walking occupants.

Most indoor air studies have not considered the influence of walking occupants. However, the occupants of many air conditioned rooms are a mixture of sedentary and walking occupants, such as in an opening plain office. In this paper, a series of tests are conducted under three air distribution methods (stratum ventilation, displacement ventilation and mixing ventilation) with a real walking occupant. The occupant walks at a speed of 1.5 m/s along two different walking routes. Velocity, temperature and CO2 concentration are measured to find the influence on air distribution. The results show that a short walk does not change the temperature or CO2 concentration profiles. When the walk lasts for a long time (30 min in this study), the walking occupant causes mixing effect. The influence under mixing ventilation is the smallest. The influence under stratum ventilation is smaller than that under displacement ventilation. The ventilation efficiency of stratum ventilation is still higher than that of mixing ventilation. Stratum ventilation and mixing ventilation recover from the influence more quickly than displacement ventilation. The results show the application potential of stratum ventilation with frequently walking occupants.