Experimental study of the heat transfers and passive cooling potential of a ventilated plenum designed for uniform air distribution

suspended ceiling to uniformly distribute the supply air to the occupied zone. This, in effect, increases the thermal mass of the room because the upper slab of the room no longer is isolated from the occupied zone.In this study, the cooling potential of a diffuse ceiling ventilation system isinvestigated by experiments focused toward characterizing the convective heattransfer of the plenum. The heat transfers are quantified from four different air flow rates, the temperature of the air supplied to the plenum and the mean surface temperature, i.e. the total heat transfer coefficient of the plenum.The established heat transfer coefficient is used for analysis of the cooling performance of the system in dynamic building simulation program which showed that during peak summer days, the scenario with ventilated plenum would exhibit temperatures in the occupied zone approx. 1-1.5 °C lower than the baseline with unventilated plenum.In conclusion this study disclosed the mean heat transfer of the plenum with an inlet jet of approx. 1.2-0.4 m/s and temperature differences of 0.5-4.5 °C and showed that ventilation supply through the plenum can be used to augment the night cooling potential.