What is displacement ventilation?
In displacement ventilation the air is supplied at a lower
temperature in relation to the room air. The air is supplied at
floor level, directly in the occupied zone.
This creates a stratified flow where the cooled supply air flows
out into the room under the warmer room air. The flow in the room
is based on natural air movements where the air is driven by a
difference in density and by convection flows from heat-releasing
activities and processes.
Convection flows at heat sources generate a vertical air flow in
the room, thereby creating a clean zone on the bottom and a
polluted zone on top.
A high level of heat activity from heat sources generates bigger
convection flows, resulting in the air rising more strongly and
greater entrainment of the air around the source.