Numerical evaluation of inclined ceiling diffuser on buoyancy and airflow patterns in an enclosed space

The effectiveness of an air-conditioning system depends on the airflow pattern inside the room. Expansions in the air conditioning systems by increasing air conditioning capacity or increasing the number of inlets were not an efficient way to achieve comfortable environment. The ideal cooling arrangement usually comes from minimizing the temperature of the air in the mixing zone and then removing the mixed air through the outlet. In the present study, the effect of inlet-outlet configuration on the airflow patterns in a room equipped with a ceiling diffuser was studied. The variation in the direction of incoming air from inlet port was analyzed. A comparison of the various cases showed that the inclination at inlet could be an essential part for the optimum configuration, as the temperature distribution in the occupied zone had least variation. The velocity distribution was almost uniform in most of the occupied zone.

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