that this person is in the enclosed space. The hotter and contaminated air
start to accumulate in the upper region of the space.
|This is the
situation where more fresher and tempered air should be provided to this
|There are two
fresher and dilute contaminant in the space by mixing and uniformize the
filed parameters (temperature, contaminant, humidity, etc.)
|2. If it is
possible that the hotter and contaminant air can be entrapped in the upper
region, the air had better be separated upper and lower region.
|For 1, we need
high velocity jet to enhance a mixing effect, therefore the location of the
terminal should be away from human occupant.
This is mixing ventilation.
|For 2, we need
the pool of the cool air at the floor level so that plume is generated
naturally. This implies that location of diffuser should be close to floor
level and since it is also close to occupants the air terminal velocity
should be low. (gravity current).