Research, development and use of displacement ventilation, mainly confined to Scandinavian countries, is now gaining popularity in other countries as well.
The guidebook serves as a comprehensive and easy-to-understand design manual. The book explains the benefits and limitations of displacement in commercial ventilation and outlines where ventilation should be applied. Case studies for a restaurant, office cubicle, auditorium, meeting room and classroom are included.
With displacement ventilation, warm contaminants rise to the ceiling, the contaminated air is extracted and fresh, cool air is supplied at floor level. Displacement ventilation has two main advantages over traditional mixing systems. First, it ensures improved indoor air quality throughout occupied spaces and removes more contaminants at high level than conventional mixing air distribution systems. Second, as an efficient use of energy due to its capability to remove exhaust air from the room at a higher temperature than that in the occupied zone, this strategy allows a higher inlet temperature for the same internal heat gain/load. Benefits are that less cooling is needed for a given temperature in the occupied spaces, longer periods with free cooling and better air quality in the occupied spaces.
The book also points out the limitations of displacement ventilation. The technique is no marvel that can solve all ventilation problems, but a principle that has definite advantages when applied correctly.