Technical feasibility of a stratum-ventilated room for multiple rows of occupants

• A room with occupants in two and three rows was studied.
• Theoretical analysis, human subject tests and CFD simulations were conducted.
• The number of rows was found not a decisive factor for performance.
• Stratum ventilation can be applied in a room with occupants in multiple rows.

This study aimed to explore the technical feasibility of stratum ventilation for a room with occupants in multiple rows. Theoretical analysis, human subject tests and computational fluid dynamics (CFD) simulations were conducted. All the results showed that stratum ventilation can be used for a room with multiple rows of occupants. Human subject tests indicated that the acceptable thermal comfort with low draft was achieved for the two rows of occupants. The CFD simulations showed that the acceptable thermal comfort level has been reached, measured by EDTS (effective draft temperature for stratum ventilation), PMV (predicted mean vote), PPD (predicted percentage dissatisfied) and PD (percentage dissatisfied due to draft), and air of young age was also achieved for the three rows of occupants. This is because the cool fresh supply air can flow around and over the front-row occupants to reach the back rows even though they establish a local blocking effect to the supply airflows. Thus, the number of rows should not be a decisive factor for stratum ventilation. Therefore, it is reasonable to expect that with properly designed air supply parameters, stratum ventilation can be applied in a room with multiple rows of occupants.