The work was concerned with measuring natural convection through a large horizontal opening between two rooms in a building. Airflow rates between the two rooms were measured using a tracer-gas decay technique. Room 1 was heated to various temperatures in the range l8°C to 33°C using thermostatically-controlled heaters. Room 2 was unheated. A multi-point sampling unit was used to collect tracer-gas samples from each room. The concentration of SF6 tracer was measured using an infra-red gas analyser.
This paper presents the results of full-scale experiments in a realistic building to evaluate natural convective heat and mass transfer through doorway-like apertures under small temperature differentials. The zone-to-zone temperature differences were nominally between re and 2.5°C. Heat transfer correlations, coefficient of discharge, and thermal stratification are reported for air (Pr = 0. 71), an enclosure aspect ratio of 0.26, aperture height relative to the enclosure height in the range of 0. 75 to l, and aperture width relative to the enclosure width in the range 0.29 to 0. 79.