A high performance linear diffuser
was placed at the end of the first tunnel to distribute conditioned air 50 ft (15 m) down the bridge.
Air first enters the space and moves downward and away from the linear diffuser
. This behavior creates a recirculation zone directly under the linear dispersion ductwork system, as shown in Figure 2.
The lab is equipped with three sensors and recreates the exhalation and body heat of passengers and an airliner's "linear diffuser
" environmental control system, which supplies fresh and recirculated air.
A rectangular linear diffuser
(Figure 2a and 2b) with two air slots is used for the ceiling installation.
In the current analysis, the ceiling return is placed right behind the ceiling linear diffuser
(with the discharge angle facing forward away from the ceiling return).
In the case of the overhead mixing system the air is supplied in the lobby area through a side bar linear diffuser
with 1 inch slot placed at a height of 11 ft all along the length of the lobby.
In fact, while I was developing criteria for a linear diffuser
in the late 1970s, I conducted more than 1,000 tests using varying temperatures and airflow rates and calculated temperature/velocity profiles for each of them.
There are very few locations where a linear diffuser
should be set to discharge down, although it seems many are set that way, likely by accident.
w.) Linear diffuser
- Adequate flow rate: 85 ~ 550 [m.sup.3]/h (50 ~ 325 cfm) - Throw height: 2.43 m (8.0 ft) at 0.3 m/s (50 fpm) with 128 [m.sup.3]/h (75 cfm) - Pressure drop: 0.127 mm.
Addressing this set of opportunities, the design team created a new, hybrid type of linear diffuser
and integrated it and all perimeter HVAC functions under one continuous linear bar grille along the outside wall.