Ventilation effectiveness in a partitioned office with displacement ventilation determined by computer simulation.

Unlike conventional ventilation systems, the displacement ventilation system supplies air in the low region of a room, while the exhaust opening is usually placed near the ceiling. When partitions are used in the occupied zone, the diffusion of supply air may be obstructed; thus, the existence of the partition may present important effects on air diffusion, retarding the removal of a contaminant. The present study considers the effects of office partition layout on air diffusion and indoor contaminant control in a large partitioned office equipped with a displacement ventilation system. The investigation was conducted by computer simulation for three-dimensional turbulent flow with a k-e two-equation model of turbulence. The average contaminant concentrations and age of air in each chamber were indicators in the evaluation of the air exchange efficiency and ventilation effectiveness under five different partition layouts. The displacement ventilation system provides fresher air to all chambers than a conventional ventilation system, and a proper arrangement of office partition can reduce the overall level by about 37%. With partitions in the office, the advantage of displacement ventilation may not be pronounced.