Abstract
Ventilation is significant to indoor air quality and human comfort in building. By increasing the air velocity, occupant would be satisfied with the thermal comfort at slightly higher temperature than the conditioned space. In present paper, the chimney made by a steel plate with 1 mm thick and 3 meter high, the square duct, where the outer surface is painted in black, is constructed and experimented. The air flow velocity was measured by the hotwire anemometer at the outlet and inlet of the chimney. The outdoor tests were carried out under the real climate condition where the solar radiation was varied throughout the day. It was found that the solar irradiation has influenced the performance of the chimney according to the temperature difference that caused the buoyancy force. The temperature difference and air velocity in the square steel chimney is presented. The experimental results show that the air temperature inside the chimney near the black surface is the highest then gradually decreases to the far distance from the black surface. It is found that the air temperature difference in the horizontal plane across the width of the chimney is up to 7 °C while the air temperature difference in the vertical direction is at 1.4 °C. As a result, the air flow near black surface of 0.26 m/s is measured. This can be used for the building ventilation even at the low height chimney.
Abstract by the authors, reproduced under the CC BY-NC-ND 4.0 licence. Original publication via the link below.