2594 -- The Performance of a Continuous Linear Air Diffuser in the Perimeter Zone of an Office Environment

A testing program was conducted to determine whether continuous linear air diffusers can provide a satisfactory thermal environment in the perimeter zones of office buildings without the assistance of convective heaters. In these laboratory tests, a movable, temperature-controlled glass wall was used to simulate a perimeter wall. Both closed office and open office configurations were tested with the diffusers parallel to the perimeter wall. A variety of internal and external heat loads were imposed on the test zone as the distance from the perimeter wall to the nearest linear diffuser was varied. As a measure of system performance, many values of air temperature and air speed for a given test configuration were used to calculate the Air Diffusion Performance Index (ADPI). Results of these tests indicate that the best performance can be obtained with a diffuser to wall spacing of 1 to 3 m (3 to 10 ft) and a volumetric supply air flow rate of about 36 1 per sec per m (23 cfm per ft) of diffuser. Overall, the test results suggest that a continuous linear diffuser can give acceptable performance (i.e., ADPI values greater than 70%) for a variety of heat loads without the use of convective or radiant heaters along the perimeter wall.