The main objectives of this study were to evaluate the air distribution performance index (ADPI) based on measured centreline data and determine the effect of turbulence on ADPI. The data were collected in a large test room (24 by 16 by 9ft [7.3 by 4.9 by 2.7m ) with a high sidewall grille. The air flow characteristics at the centreline of the room for 21 test cases under both isothermal and nonisothermal flow conditions were investigated. The results showed that ADPI values determined using the "centreline" data and the "whole room" data were approximately the same. The ADPI results were strongly dependent on the room heat load and the air flow rate. The effect of turbulence on ADPI was investigated using a comfort model, and a modified ADPI model was presented. The results showed that the turbulence intensity strongly affected ADPI values at high air flow rates.

KEYWORDS: year 1996, calculating, turbulent flow, air distribution, properties, air flow, measuring, calculating, rooms, heat load, air flow rate, air movement, draughts