Velocity Distribution in a Room Ventilated by Displacement Ventilation and Wall-Mounted Air Terminal Devices

The article describes experiments with wall-mounted air terminal devices. The airflow from an air terminal device influences the occupants' thermal comfort and, therefore, it is important to develop an expression for this flow in the occupied zone. The velocity at the floor is influenced by the flow rate to the room, the temperature difference and the type of diffuser. The flow is stratified at Archimedes numbers larger than four. The article gives expressions for the velocity distribution close to the floor. It is shown that openings between obstacles placed directly on the floor generate a flow similar to the air movement in front of a diffuser, and expressions for the velocity distribution in that situation are also given in the article