To compare the ventilation performance of the displacement ventilation
cases with 4 ach, this paper shows the averaged contaminant concentrations at the breathing level of sitting and standing positions--i.e., at the breathing levels of a sitting person (3.7 ft [1.1 m] above the floor) and a standing person (5.3 ft or [1.6 m] above the floor).
No or very small and efficient HVAC, depending on the climate, and underfloor displacement ventilation
has received significant attention in building designs in recent years.
In the case of the displacement ventilation
system the air is supplied through two displacement diffusers: 30 in x 60 in x 14in) located on the two ventilation shafts in the lobby area with the front and sides of the diffusers as supply areas (Figure 1).
This paper reports a study of indoor environment conditions in an office room equipped with floor heating and displacement ventilation
. A CFD model was developed using data from a full-scale experimental model.
A dedicated, 100% outdoor air, ventilation system is used in conjunction with natural and displacement ventilation
strategies to reduce the demand on the central plant, while improving ventilation distribution and occupant comfort.
Stratified ventilation, including displacement ventilation
(DV) and underfloor air distribution (UFAD), is a means of providing cool supply air directly to the vicinity of occupants in a space.
The ventilation effectiveness measured with PV systems is reported to be higher than the ventilation effectiveness typically encountered when observing mixing or displacement ventilation
systems (Melikov et al.
Later, in a study by Chen (2) in 2009, a procedure for verification of CFD analysis was developed, which showed it was possible to accurately predict the performance of displacement ventilation
2)Hybrid ventilation of the mall central spaces, where natural displacement ventilation
at higher than minimum volumes can help free-cool these areas until there is a risk of overheating.
We also have a fascinating feature about how a century-old building used displacement ventilation
to improve indoor air quality and thermal comfort.
In displacement ventilation
systems, as opposed to the traditional overhead supply mixing ventilation systems, cold air which is supplied at low velocity near the floor captures sensible heat from the space, rises due to buoyancy, and creates stratified temperature distribution in the space.