Design methods for displacement ventilation: Critical review.
Displacement ventilation has been successfully applied for more than twenty years in Europe and it represents an opportunity for China.
Displacement ventilation (DV) is based on vertical stratification of temperature in the occupied zone of rooms. Buoyancy flows generated by heat sources govern the air distribution in rooms with DV. If properly designed DV has potential to provide higher ventilation effectiveness, i.e. better inhaled air quality for occupants and lower energy consumption than mixing ventilation.
In order to avoid thermal discomfort due to draughts and vertical temperature difference, the temperature distribution should be carefully predicted in the design stage. The REHVA and ASHRAE methods to design displacement ventilation systems for thermal comfort are introduced in this paper and critically reviewed.